Yet Another Study Shows the Real Dangers of Raw Diets for Dogs

I have covered the raw diet issues since the very start of this blog, which is about nine years now. My articles on the subject are collected here. Very little has changed in my assessment of the evidence over this time. The bottom line is clear:

There is evidence of risk in feeding raw, including infectious disease, parasites, and injury from raw bones. There is no scientific evidence, only anecdote and dubious theories, to demonstrate any benefits from feeding raw.

A new study has recently been published which adds to the already considerable evidence of risk from infectious disease.

Martinez-Anton, L., Marenda, M., Firestone, S.M., Bushell, R.N., Child, G., Hamilton, A.I., Long, S.N. and Le Chevoir, M.A.R. (2018), Investigation of the Role of Campylobacter Infection in Suspected Acute Polyradiculoneuritis in Dogs. J Vet Intern Med, 32: 352–360.

This was a case control study conducted in Australia and designed to look for associations between the occurrence of a serious neurologic disease, Acute Polyradiculoneuritis (APN) and infection with the bacterium Campylobacter sp. This bacterium has been identified as a common trigger for the analogous disease in humans, Guillain-Barré Syndrome. Because exposure to raw chicken is a common source of Campylobacter infection in humans, the feeding of raw chicken, and other raw meats, was one of the variables evaluated in this study.

The results were quite clear. Dogs with APN were far more likely to be have Campylobacter than healthy dogs, and dogs with APN were also much more likely to have been fed raw chicken and other raw foods.

This type of study only shows an association, not a definitive cause-effect relationship. A prospective randomized controlled trial would be needed to prove feeding raw chicken can cause Campylobacter infection which can then cause APN. However, such studies are not always necessary or appropriate to guide us in reducing our risk of disease. Case-control studies are the main source of evidence showing smoking increases the risk of lung cancer, and certainly a randomized trial in which some people are made to smoke for years and others are not to definitively prove this relationship would be unnecessary and unethical.

We are more often willing to inflict harm on animals in order to investigate the causes of disease, so it is possible someone will do such a study in dogs even though we would not do it in humans. However, it is clear that this study, in the context of the existing evidence in veterinary and human medicine, supports the clear health risks eating raw meat.

Proponents of raw diets will certainly argue that the risk is small compared to the benefits. Unfortunately, no scientific evidence yet exists to show any benefits, and personal anecdotes or theories about the natural history of dogs are not sufficient reason to ignore the robust scientific evidence of the harm that raw diets can cause. Unless some reliable research evidence emerges to show meaningful health benefits from raw feeding, there is no good reason for pet owners to participate in this dangerous fad.


Posted in Nutrition | 50 Comments

FDA Proposed Updated Regulation of Homeopathy- Time to Comment Again!

The wheels of government turn slowly, but they turn. Over the last several years, we’ve seen a number of governments around the world catch up to the science that shows homeopathy is worthless quackery. In Europe, the UK, and Australia, both human and veterinary medical organizations have been acknowledging this simple fact and taken steps to discourage people from being fooled into using this pointless treatment. Even here in the US, where regulation in general is widely resisted and there is robust anti-science sentiment in many quarters, the Federal Trade Commission (FTC) has acknowledge that homeopathy is nothing more than a placebo and should not be marketed as effective medicine. Such consistent, broad-based progress gives me reason for hope that science and reason can still have a positive impact on people’s beliefs and actions.

One critical agency that has chosen to re-examine how it regulates homeopathy is the Food and Drug Administration (FDA). Under the standards the FDA uses to determine whether medicines can be sold as safe and effective, homeopathy could never be allowed. Unfortunately, a politician who was a homeopath snuck the practice into the original law establishing the FDA in 1938. The last time the FDA reviewed its non-regulation of homeopathy, in 1988, it chose to continue the practice to be used regardless of the evidence it is ineffective.

In March, 2015, I wrote about a public comment process the FDA had initiated in order to review its regulation of homeopathy. More than two years later, the FDA has issued a draft guidance updating that issued in 1988. This document does not establish legal mandates regarding homeopathy, but indicates the general posture of the agency towards the subject and hints at what kinds of actions the FDA might be willing to take in the future.

What I recommended in my comments to the agency in 2015 was the following:

  1. Draft and submit to Congress a report identifying homeopathy as ineffective and recommending changes in the agency’s authorizing legislation to prohibit the marketing and use of homeopathy without fulfillment of the same new drug licensing requirements applied conventional drugs.
  2. Produce educational materials for healthcare providers and patients in both human and animal health fields identifying the ineffective nature of homeopathy for the treatment or prevention of human and animal disease.
  3. Require all OTC homeopathic products to carry a label similar to that required for dietary supplements under DSHEA, “This/these statement(s) have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.”
  4. Vigorously enforce regulations in both human and animal health fields prohibiting treatment and prevention claims for homeopathic remedies without fulfillment of the requirements of a NDA.


Not surprisingly, the draft guidance doesn’t go nearly as far as I would have liked. Still, it is an improvement on the existing policy, and it might help reduce the harm done by homeopathy if it is actually carried out.

The agency begins by asserting that it has authority to regulate homeopathic products and that it could, if it chose, prohibit the marketing of any without completion of a new drug application requiring the same standards of proof for safety and efficacy as required for real medicine:

…all drug products labeled as homeopathic are subject to the premarket approval requirements in section 505 of the FD&C Act or section 351 of the PHS Act. There are no drug products labeled as homeopathic that are approved by FDA.

The FDA further acknowledges that the failure of homeopathic remedies to be held to this standard means they cannot be considered safe and effective and that this presents a potential hazard to public health:

Drugs marketed without required FDA approval may not meet modern standards for safety, effectiveness, quality, and labeling. The continued marketing of products that have neither been approved by FDA nor found to be 82 GRAS/E is a public health concern.

While the FDA does not yet intend to require this standard of evidence, this guidance makes it clear that it could and that no homeopathic remedy has ever met this standard. Instead, the FDA indicates that it considers some homeopathic practices more dangerous than others and intends to focus on discouraging those most likely to cause harm:

The Agency generally intends to apply a risk-based enforcement approach to the manufacturing, distribution, and marketing of drug products labeled as homeopathic…FDA intends to prioritize enforcement and regulatory actions involving drug products labeled as homeopathic and marketed without the required FDA approval in the following categories:

  • Products with reported safety concerns. For example, MedWatch reports or other information submitted to the Agency can indicate or signal a potential association between the product and an adverse event, medication errors, or other safety issues.
  • Products that contain or purport to contain ingredients associated with potentially significant safety concerns. For example, potentially significant safety concerns are raised by products that contain or purport to contain:
  • An infectious agent with the potential to be pathogenic
  • A controlled substance, as defined in the Controlled Substances Act, 21 U.S.C. 147 812; 148
  • Multiple ingredients that, when used in combination, raise safety concerns due to possible interactions, synergistic effects, or additive effects of the various ingredients
  • Ingredients that pose potential toxic effects, particularly when those ingredients are concentrated or in low dilution presentations (e.g., 1X, 2X, or 1C), or are not adequately controlled in the manufacturing process.
  • Products for routes of administration other than oral and topical. For example, unapproved injectable drug products and unapproved ophthalmic drug products pose a greater risk of harm to users due to their routes of administration (e.g., bypassing some of the body’s natural defenses, differences in absorption) and the potential risk of harm from contamination.
  • Products intended to be used for the prevention or treatment of serious and/or life-threatening diseases and conditions. Unapproved products for serious and/or life-threatening diseases and conditions raise public health concerns, in part, because they may cause users to delay or discontinue medical treatments that have been found safe and effective through the NDA or BLA approval processes.
  • Products for vulnerable populations. For example, patient populations such as immunocompromised individuals, infants and children, the elderly, and pregnant women may be at greater risk for adverse reactions associated with a drug product, even if it contains only small amounts of an ingredient, due to their varying ability to absorb, metabolize, distribute, or excrete the product or its metabolites. These populations may also be at greater risk of harm as a result of foregoing the use of medical treatments that have been found safe and effective through the NDA or BLA approval processes or under the OTC Drug Review.


What all this means is that the FDA recognizes the main causes of harm from homeopathy: direct harm from remedies made improperly or containing dangerous ingredients and indirect harm from delayed diagnosis and effective treatment. The agency is not interested in banning over-the-counter sugar pills used to treat mild, self-limiting problems, but it is willing to intervene when homeopaths make remedies that are actively harmful or when they try to sell them to people who are really sick and need real medical care. It remains to be seen how willing the agency is to enforce such standards if they are adopted.

The next step is for the public to weigh in on this guidance. As usual, the highly motivated proponents of homeopathy are likely to be dis-proportionally represented in such public input. However, the very existence of this draft guidelines suggests that substantive, evidence-based input did have an influence on the FDA during the previous comment period, so we should all continue to participate in this process.

Eventually, comments will be accepted online at I will update this post when the comment page is available.




Posted in Homeopathy, Law, Regulation, and Politics | 3 Comments

Trump Leading the Charge Against Science and Reality

The focus of this blog is science, and the role of science in medicine, especially veterinary medicine. However, politics, law, and other non-scientific fields are covered from time to time when they impact the core subjects of science and medicine.  I have covered more politics than usual in the last year primarily because of the unprecedented attacks against science, and the entire edifice of Enlightenment thinking, that have made modern medicine, and the civilization as we know it, possible. This is a unique and dangerous time here in the United States, and the predominant threat to science and medicine now comes not from post-modernist ideology or the infiltration of faith-based visions of so-called alternative medicine into mainstream medical science, but from the open hostility towards science and the very concepts of facts and truth exhibited by the individuals running much of our national government.

I first  wrote about Donald Trump’s anti-science views a little over a year ago, before he was elected president. While all the candidates had some questionable views on at least one scientific topic, Trump set himself apart with his climate change denialism and his embracing of anti-vaccine activists. Andrew Wakefield and several of the most extreme quacks I’ve written about here proudly endorsed him for this.

Since the election, science advocacy groups have highlighted the many ways in which Trump and his administration have led a full assault on science. Six months into his term, the Union of Concerned Scientists reported on the anti-science activities of the administration:

  • Sidelining independent science advice. The Trump administration has weakened federal advisory committees that provide scientific advice to the government.
  • Appointing conflicted individuals to scientific leadership positions. President Trump has appointed to the highest positions in government individuals with little science background and with strong ties to the industries they are charged with regulating.
  • Leaving key science positions vacant. President Trump has taken an unusually long time to fill many high-level science positions, signaling the low priority his administration places on science.
  • Revoking science-based safeguards. Aided and abetted by Congress, President Trump has allowed politics to supersede science by signing an unprecedented 13 congressional resolutions rolling back science-based protections, including safe drinking water standards and safeguards to prevent worker exposure to harmful chemicals.
  • Misrepresenting climate science and rolling back climate change safeguards. Attacking science-based policies and communications on preparing for and mitigating climate change is a clear focus for the Trump administration. Officials have misrepresented climate science, removed climate-related content from several government communications, and proposed sharp reductions in climate research.
  • Weakening science-based pollution standards without scientific justification. The administration has delayed or repealed several science-based pollution standards designed to protect public health, including protections against mercury, air toxics, and coal wastewater, without replacing them with new, scientifically defensible standards.
  • Undermining protections from hazards at work and home. The Trump administration has delayed many science-based rules intended to keep communities safe from dangerous chemical spills and to safeguard workers from harmful toxins, with little to support halts except for letters and petitions from companies or industry trade associations.
  • Altering scientific content on federal websites. The scientific content of federal agency webpages, including those of the Environmental Protection Agency, the State Department, and the Department of Energy, has been altered or deleted since January, particularly in regard to climate change science.
  • Reducing public access to data. The Trump administration has reduced public access to scientific data and information. The administration also has stopped collecting certain data for programs that benefit disadvantaged groups. And it has withdrawn requests to industry to supply data that would help inform public health and environmental protections.
  • Restricting communication of scientists. The Trump administration is making it more difficult for government scientists to speak publicly about their work, as well as about misconduct within an agency. It has restricted communication with Congress, placed vague gag orders on agency staff, and failed to affirm the ability of scientists to share their expertise publicly.
  • Creating a hostile environment for scientific staff. Evidence is growing that a culture of fear is increasing at government agencies, undermining scientific research and communication. Scientists are speaking to the media anonymously out of fear of retaliation; some are afraid to utter the words “climate change.”

Many news organizations have reported on how Trump and his appointees are ignoring and attacking science, including:

The New York Times

The LA Times

The Guardian


The latest article, from the Washington Post, illustrates the administration’s open and clear desire to suppress any scientific research or thought that might conflict with the ideology and agenda of the Trump White House. It also illustrates an Orwellian approach of demeaning the very concept of truth and trying to control language so as to control thought. The following headline should have been from a satirical news source like The Onion, but it is, in fact, a direct report of an actual Trump administration policy:

Trump administration gives CDC a list of forbidden words, including “fetus,” “transgender,” and “evidence-based.”

The full list of words the Centers for Disease Control (CDC) are forbidden from using in official documents being prepared for next year’s budget is as follows:


You might have noticed a couple of my favorites on that list. Fortunately, I don’t work for the CDC, so I will continue to talk about “evidence-based” and “science-based” medicine. The fact that anyone could believe it is in the best interests of the public to prevent public health scientists from talking about these subjects, however, is bizarre and terrifying.

All politicians, and really all human beings, will sometimes dismiss or ignore science when it conflicts with their beliefs or ideology. But Donald Trump goes well beyond such normal human failings. He appears to truly believe that suppressing science and destroying confidence in the concepts of objective truth and simple facts is the right thing to do if it gets him what he wants.

What it will really get us, if successful, is a return to the pre-Enlightenment darkness of superstition and faith without reason or true understanding. I have talked about the Age of Endarkenment before, when I was disappointed by the triumph of politics and belief over reason and science. In the past, it was merely a poetic turn of phrase to describe my sense that progress towards ever more accurate and effective science-based understanding of nature, and the application of this understanding in medicine, was less steady than I would like. Now, I have to honestly wonder if it might be a more accurate description of the future of my country than I ever dreamed, even at my most cynical. Certainly, it is a vision some in the government appear to desire rather than fear.

The great science advocate Bill Nye has referred to Trump and his administration as “the last gasp of the anti-science movement.” He seems confident that we are, as a people, not stupid enough to buy the toxic bullshit trump is selling. I can’t say as I share that confidence, but I will try to have hope. I will certainly try to defend science against the latest assault, as I have against less potent ones before, because I believe it is our best bet for understanding the universe and for improving our lot in it.

Posted in Law, Regulation, and Politics | 6 Comments

Colloidal Silver- Colorful Snake Oil but not Medicine

Colloidal silver illustrates many of the classic characteristics of quack alternative medicines. It has a history of mainstream use based on tradition and theory, but it was abandoned by science-based medicine in favor of safer and more effective treatments. There are a few legitimate uses of silver-containing compounds, and these are misrepresented as supporting inappropriate uses of these and other silver-containing substances. There is some laboratory research that shows biologic effects of silver in test tubes, and this too is misused to justify giving silver products to sick patients. There is virtually no research on colloidal silver in actual patient, and what there is fails to meet basic standards of quality. There are, however, lots of anecdotes which people wrongly believe can be used to support treatment with this snake oil.

Colloidal silver is a liquid, usually water, with microscopic particles of silver suspended in it. While some medical uses of silver are legitimate, none involve oral colloidal silver. Topical use of ointments for burns and to prevent eye infections in newborns, and impregnation of catheters and other medical equipment with silver, do have some benefits. However, taking colloidal silver orally is an entirely different thing, and there are no proven benefits from this practice. There are, however, significant risks.

I haven’t previously covered this topic because the risks and lack of benefits from colloidal silver have been thoroughly covered elsewhere, and fortunately it is not at the top of the list for alternative treatments of pets. However, a reader recently drew my attention to a “study” of colloidal silver in dogs. As poorly conducted and unreliable as this paper is, undoubtedly some will claim it as evidence supporting the use of colloidal silver in dogs, so I felt it was worth discussing why it is not.

First, though, here are a few sources discussing the lack of benefits and the real risks of colloidal silver in humans:


There are no high quality studies on the health effects of taking colloidal silver, but we do have good evidence of its dangers.

Silver has no known function or benefits in the body when taken by mouth.

Silver is not a nutritionally essential mineral or a useful dietary supplement.

There are no legally marketed prescription or over-the-counter drugs containing colloidal silver that are taken by mouth.
National Center for Complementary and Integrative Health

All over-the-counter (OTC) drug products containing colloidal silver ingredients or silver for internal or external use are not generally recognized as safe and effective and are misbranded. FDA is issuing this final rule because many OTC drug products containing colloidal silver ingredients or silver salts are being marketed for numerous serious disease conditions and FDA is not aware of any substantial scientific evidence that supports the use of OTC colloidal silver ingredients or silver salts for these disease conditions.
Food and Drug Administration

Colloidal silver isn’t considered safe or effective for any of the health claims manufacturers make. Silver has no known purpose in the body. Nor is it an essential mineral, as some sellers of silver products claim.
Mayo Clinic

There is no data to support silver to treat infections.

So for what diseases is there evidence for which colloidal silver is efficacious? Well, nothing.  Pubmed is silent on taking colloidal silver to benefit any disease, infection or otherwise. There are no clinical trials to show efficacy. Nothing.
Science-based Medicine 


When taken orally, silver can interact with and reduce the effectiveness of tetracycline, quinolone, and penicillamine. Long term use can cause silver deposition in the skin and mucous membranes leading to an irreversible condition called argyria, characterized by bluish-gray to gray-black pigmentation. Other adverse effects include seizures (6) and kidney damage. Pregnant women should not consume colloidal silver as it can cause developmental abnormalities in the fetus.
Memorial Sloan-Kettering Cancer Center

Colloidal silver can cause serious side effects. The most common is argyria, a bluish-gray discoloration of the skin, which is usually permanent.

Colloidal silver can also cause poor absorption of some drugs, such as certain antibiotics and thyroxine (used to treat thyroid deficiency).
National Center for Complementary and Integrative Health

Brain and nerve damage from silver exposure is rare, but colloidal silver can cause kidney damage, stomach distress, and headaches.

The most common problem associated with silver exposure is argyria: The skin turns a bluish gray as granules of silver accumulate in the body.
Harvard Medical School

So we have a product with no proven benefits, only anecdotal claims and inappropriate extrapolation from lab studies. We also have proven significant risks. Seems like a pretty clear case for abandoning the treatment, as science-based medicine has done. Unfortunately. It is still easy to find alternative practitioners recommending colloidal silver, for veterinary patients as well as for people.

A Veterinary “Study” of Colloidal Silver
These practitioners may be tempted to claim validation from a paper published last year. This “study” failed to meet even the most basic standards of clinical research, which is probably why it was published in a nanotechnology journal rather than a medical journal. It is effectively a collection of anecdotes dressed in the trappings of scientific research, and it does not justify using colloidal silver in dogs.

Bogdanchikova N. Vázquez-Muñoz R. Huerta-Saquero A. et al. Silver nanoparticles composition for treatment of distemper in dogs. International Journal of Nanotechnology. 2016;13(1-3):227-237.

The paper reports a comparison of dogs with canine distemper, a viral infection, treated with colloidal silver or with standard medical treatment for this disease. It purports to show that silver improved the survival of dogs with distemper as long as they did not have neurologic symptoms. Dogs without such symptoms who were treated with silver appeared to be more likely to survive the disease than dogs without neurologic signs who received standard care. The authors then confidently claim silver was effective in treating dogs with distemper as long as they did not have the neurologic form of the disease.

It would be fantastic if this were true since standard care is not very effective for many dogs with canine distemper. Unfortunately, there are very many reasons why this study cannot, in fact, support the claims the authors have made for colloidal silver. To explain this, I will briefly review how scientific research is supposed to be different from mere anecdote, and why this paper doesn’t meet the basic criteria for reliable research.

I’ve discussed at length previously why stories, sometimes called anecdotal evidence, are not reliable for judging the safety of effectiveness of medical treatments or the causes of disease. Scientific research, while still imperfect, does a better job because it has methods built into it which compensate for common flaws and limitations in human observation and judgment. In clinical trials designed to test medical treatments, these methods include:

Randomization of patients– When comparing two groups, one of which gets a treatment and one which does not, the patients in the groups must be as similar as possible in every way except for the treatment, Otherwise, differences between them might be due to something other than the treatment being tested. Assigning patients to groups randomly, that is by chance, helps ensure the groups are comparable. Any way of assigning patients that is not completely left to chance introduces bias into the study.

Blinding to randomization– Since all our choices and decisions are unconsciously, if not consciously, biased by our existing beliefs, if we are aware of who gets assigned to the test treatment or the comparison group, we can influence this in a way that defeats the purpose of randomization. For this reason, clinical trials require that people involved in the trial don’t know which group any patient is assigned to (they are “blinded” in the language of medical research).

Blinding to treatment– Just as people in the study shouldn’t know which group patients are assigned to, they also shouldn’t know which treatment people are getting. Anyone treating or evaluating patients who knows which group they are in will inevitably unconsciously skew their actions and the results in favor of the outcome they expect or hope for.

Statistical comparisons– Various kinds of mathematical tests are used to compare differences between groups to help identify how likely those differences are to be due to chance rather than the treatment. These methods have many flaws and limitations, but they help make research results more reliable than simple observation.

The paper which claims to report a research study comparing dogs with canine distemper infections treated with colloidal silver and those treated with standard medical care does not meet even these basic criteria for a controlled clinical trial. It looks like a scientific study, but without these controls for bias, it is simply a collection of anecdotes.

To begin with, dogs were assigned to colloidal silver treatment or standard care based on whether or not their owners were offered silver treatment and agreed to allow it. There is nothing random about this. The doctors and the owners simply decided who would get the experimental treatment and who wouldn’t, which guarantees the patients will differ in ways likely to affect the outcome. If, for example, owners of sicker dogs were afraid to try an experimental treatment while owners whose dogs were not as ill were more willing to accept it, then dogs in the control group would automatically be sicker, and have worse outcomes, than dogs in the treatment group. This is just one of many ways in which the lack of randomization or blinding to randomization could influence the results of this study.

There is also no indication that owners, caregivers, or research personnel were blinded to which group patients were part of. If this is true, the lack of this most basic control for bias means the people involved in the study could have intentionally or unconsciously influence the results in many ways.

There were certainly no statistical comparisons made in the paper. It is possible that even the authors recognized that the lack of standard methods for controlling bias and error in the study made any such mathematical comparison inappropriate and meaningless. However, it may also be that they felt the results were so clear and obvious that statistical comparisons were unnecessary. In either case, the lack of these comparisons further reduces the reliability of the results.

There are a number of other serious problems with this paper, some of which have to do with the nature of canine distemper infection and how it is diagnosed and treated. Canine distemper virus (CDV) affects different dogs differently. Many do not develop serious illness at all. Puppies get sicker than older dogs, and dogs with other diseases or poor immune system function are more likely to get seriously ill or die than healthier dogs. Different strains of the virus also produce different degrees of illness. All of these variations mean that the course of illness and chances of survival vary greatly between dogs. This is exactly the kind of variation that requires randomization and blinding to randomization to ensure that study subjects getting different treatments are truly comparable. Without these controls, it is quite likely that dogs getting silver treatment were different in relevant ways from dogs not getting silver, and any differences in survival could easily be due to these other differences.

It is even possible that some of the dogs in this study did not have CDV at all. There are other diseases that can similar to those of CDV, especially when there is no neurologic involvement. symptoms. The more typical symptoms a dog has, and the more consistent their physical exam findings and lab tests are with CDV, the more likely they are to have the disease. Dogs with respiratory and gastrointestinal signs who do not have neurologic disease may actually have other causes of illness, not CDV.

These are precisely the dogs in this study who appeared to recover with silver treatment. While the authors did test for antibodies to CDV, these can also be found in dogs with CDV who are sick for other reasons and in dogs who have been recently vaccinated for CDV. Very few other clinical findings or lab tests were reported to support the diagnosis. The design of this study, therefore, does not allow us to say with any certainty that the dogs who fared better did so because of the treatment. It is also possible they may not have had as severe a form of the disease as the dogs who died, or that they didn’t have CDV at all.

The death rate for CDV is also highly variable. Studies have suggested from 50-80% of dogs with distemper will die. However, most animals with mild symptoms will recover, adults are much less likely to die than puppies, and dogs with neurologic signs have a higher mortality rate than those without. Therefore, comparisons of mortality between groups treated differently must account for these differences, which was not done in this study.

As an example, while dogs without neurologic signs were similar in average age between the two groups (19 months for the silver group and 14 months for standard treatment), the ages of dogs in these groups with neurologic symptoms were very different (14 months on average for the silver group and 40 months for the standard treatment). Age is one factor that influences the likelihood of CDV and the mortality rate, so such differences can influence differences in outcomes regardless of the treatment given.

As mentioned before, dogs were assigned to standard treatment or silver based on the choices of owners and investigators. It is likely the severity of illness would differ between groups when patients are assigned in this way. Also, the type of treatment within the silver group varied, with sicker animals getting treatment more often and during a different period of time. This further complicates any attempt to compare groups.

Mortality rates differed between the treatment groups, which is the main basis for the claim that the colloidal silver had some effect. However, given the failure to ensure the groups were truly comparable, these differences can’t be used to determine if there is any effect from the treatment. All but one of the dogs with neurologic symptoms died regardless of treatment. All of the dogs with other symptoms also died with standard care, while all of the dogs with non-neurologic signs survived in the silver group. This would be a dramatic difference if it were seen in a study with appropriate methods and more than the 9 animals in the treatment group. With these limitations, unfortunately, this apparent difference is meaningless, a mere anecdote rather than a true scientific comparison.

Bottom Line
Colloidal silver has been abandoned as a medical treatment by mainstream medicine because there is no reason to believe it works and it is clear it has significant risks. While silver has some effect on infectious disease organisms in test tube studies, so do bleach and gamma radiation. This doesn’t mean any of them are appropriate as treatments for infection in living patients. There is no good clinical research evidence to justify using colloidal silver in humans or veterinary species. The research that is available, such as the study of colloidal silver in dogs with presumed canine distemper, is inadequate to draw conclusions and amounts to anecdotes made to look like scientific research.


Posted in Herbs and Supplements | 4 Comments

Herbalists Apply for Medical Specialty Recognition- An Update

I have been covering the application of the American College of Veterinary Botanical Medicine (ACVBM) for recognition as a specialty in several posts throughout the year (1, 2). My conclusion is that this recognition is not justified for several reasons:

  1. There is very little high-quality or reliable scientific evidence to support the use of herbal products in veterinary patients.
  2. Herbal prescribing is dominated by Chinese Medicine, Ayurveda, and other unscientific folk belief systems, and those proponents who take a more scientific approach are a small minority generally unwilling to reject the claims or methods of alternative herbal medicine.
  3. Herbal products are unregulated, inconsistent and unpredictable in their chemical composition, frequently contaminated with toxins or even undisclosed pharmaceutical drugs, and almost none have been properly tested for safety or efficacy. There is ample evidence of serious harm to human patients from herbal products. The ACVBM supports industry self-regulation rather than the kind of government oversight accepted as necessary for pharmaceutical medicines without any sound reason for doing so.
  4. The majority of the leadership of the ACVBM are dedicated proponents of alternative medicine, not only for herbal products but homeopathy, acupuncture, energy medicine, and many other unproven or pseudoscientific practices. Many have said clear and troubling things that display a contempt for science and science-based medicine and a desire to use the appearance of scientific methods to gain acceptance for alternative practices. This makes it very likely that approval of the ACVBM as a specialty board would serve as a Trojan horse for the legitimization of other alternative therapies.
  5. The potential of herbal medicines would be better explored from a rigorously scientific approach involving specialists in pharmacology, toxicology, nutrition, epidemiology, and other existing medical specialties.

The ACVBM has just released a revised version of their application. While I haven’t exhaustively compared this to previous versions, a couple of sections caught my interest because they directly address some of my concerns and also because they further illustrate the perspective of the group regarding the key issues of science and evidence.

Some material has been added to emphasize why the ACVBM should be a separate specialty college rather than investigating herbal treatments under the auspices of existing specialties.

Veterinary botanical medicine is a distinct discipline that differs in substance, methodology and philosophy from conventional veterinary medicine.

I will briefly comment on some of the specific arguments made to justify this claim.

While many conventional drugs are derived from plants, a veterinarian who prescribes botanical medicine is using whole herbs in preference to isolated active constituents. The whole herb or extracted herb is complex, containing hundreds of constituents that have complex actions…Veterinary herbalists are aware of differences in plant chemistry that may result from the plant’s origins.

The first half of this statement is certainly correct. Whole plants and herbal combinations are chemically very complex. This is usually identified as an advantage (as will be seen below), but it is actually one of the reasons herbal medicine is problematic. The consistency, efficacy, and safety of such complex combinations with variable ratios of different compounds that depend on multiple factors makes it very difficult to accurately predict the effects of such remedies. Herbalists claim to have specialized expertise in doing so, but when investigated these claims amount only to a belief that personal clinical experience or folk medicine traditions are reliable information, which is manifestly untrue more often than not.

That the whole plant is more therapeutic than a constituent is a fundamental principle of botanical medicine supported by research.

Well, the first half of this statement is true as well, but the second half is not. Herbalists believe whole plants to be better than isolated compounds (also known as medicine), but they have in no way proven this through research.  There are studies that show combinations of plant chemicals to be more effective in some uses than each used separately. Most of this is experimental research rather than clinical studies, which is important since the use of such combinations in actual patients is significantly more complex and uncertain.

The idea that combinations of chemicals may have greater effect than the same chemicals used separately is not all that surprising or unique to herbal medicine. Combination regimes of chemotherapy are often more effective than single-drug treatment. And some infections require multiple antibiotics given together to address all the pathogenic organisms involved. However, this does not prove some kind of general principle that combinations are always safer or more effective than single agents. It is equally likely that combinations may have greater toxicity (as if often the case when conventional medicines are used in combination), and sometimes they may interfere with one another. The fact that the compounds occur naturally together in a plant is no reason to imagine we can assume they are better as medicine when given together.

The principle of synergism may turn out to be true in many, some, or only few cases, but these need to be validated through clinical research. The assumption that this is true stems from pre-scientific folk beliefs about “natural” remedies or religious notions that God has provided for the needs of human beings by packaging remedies for our ills in nature. These beliefs have not been validated scientifically despite the claims to the contrary. Many interesting hypotheses are advanced in the application for how herbal combinations could potentially be more effective or safer than isolated compounds, but these are just hypotheses, not the established fact claimed in the document.

The application goes on to respond to concerns about the use of folk myth and pre-scientific tradition rather than science in the use of herbal remedies. The ACVBM is clearly trying to mitigate the impression that herbalists rely primarily on “traditional knowledge” rather than science in their practice.

The ACVBM differentiates themselves by interest in the rich knowledge base of traditional botanical medicine use and ethnobotany combined with modern scientific, chemical, toxicological, pharmacological clinical application and research in a practice that could be appropriately termed rationale phytotherapy to distinguish from colleagues who may only embrace traditional findings or who may eschew scientific findings. This is an evidence-based system that encourages in vitro and in vivo studies to explain mechanisms of action, pathophysiology, pharmacokinetics and bioavailability as well as efficacy of botanical medicines.

This is the application of plant based medicine (supported by science and/or traditional use) to conventional diagnosis, multiple diagnoses and complex cases and to address individual signs and problem lists; or for prevention of disease by protecting organ health and /or optimizing animal health through actions not available with conventional drugs.

I certainly believe that the best hope for making effective use of the potential in plant compounds as medicines is in a strong scientific approach, one that views traditional use only as a weak foundation for hypotheses to test, not as a sufficient basis for clinical practice. I am, however, not convinced that the ACVBM as a whole truly embraces this view. I have investigated the public statements are claims of the members of the Organizing Committee in detail, and I have followed many of them for years. A couple seems genuinely interested in bringing scientific rigor to the field. Most, however, have been quite consistent in expressing the view that science is useful only when is supports their beliefs, derived primarily from personal experience and tradition, and that scientific invalidation of anything they “know” already is nearly impossible. Science is more of a marketing tool, to convince the skeptics, not a path to testing and questioning their own views rigorously and sincerely. There are hints of this even in this document, despite efforts to suggest agreement with the view than science is necessary and tradition merely a jumping-off point.

Veterinarians using botanical medicine have a patient centered approach, whereby the botanical medicines are selected based on the individual signs and pathophysiology as well as the diagnosis. So that two dogs with diabetes for example, may be treated with two different sets of botanical medicines.

What they don’t say here is that this “individualization” is not based on scientifically established knowledge but folk tradition, personal experience, and gut feelings.

The document also discusses various sources of information in detail, with an obvious effort to rationalize the role of tradition and personal experience in the absence of significant reliable scientific evidence. This is not inherently mistaken, since the same sources of information are used in conventional medicine, and we always have to balance the availability of information against its reliability. Personal experience is easy to find but highly unreliable. Consistent, high-quality clinical research is a lot better but a lot harder to come by.

Traditional use-
The bewildering variety of ethnoveterinary practices, ethnobotanical uses and folk practices around the world coupled with confounding aspects of cultural, placebo and other non-specific effects make reliable conclusions from any one tradition difficult. Frequently however, traditional use informs research and pharmacological activity is often found to be closely correlated. There are recurring themes in traditional medicine and persistent therapeutic approaches consistent with the use of “archetypal” chemical groups within plants.

Contrary to the implications here, traditional folk practices do not consistently or accurately predict the pharmacology or clinical effects of plant chemicals. The vast majority of traditional herbal uses have not been tested. Many of these, however, make absolutely no sense and so are unlikely to be a productive foundation for research. The idea of sympathetic magic, that if things which have superficial similarities these can predict deeper connections with therapeutic value, is clearly nonsense. Plants that may resemble a penis in some people’s eyes do not consistently turn out to be aphrodisiacs. Plants that are wrinkled like the brain or lobed like the lungs or that otherwise have some subjective superficial similarity to an organ in the body do not turn out to be plants with medical value for treating diseases of those organs, despite many folk medicine traditions holding this belief.

And systems which are arbitrary and unconnected with scientific reality are not good predictors of the medical value of plants used in those systems. Chinese medicine, for example, emphasizes the balance of imaginary forces, such as Heat, Wind, Damp, etc. Other systems, such as Western Humoral Medicine and the related Indian Ayurvedic approach, also emphasize balancing various forces to achieve or restore health. However, the forces involved are imaginary constructs that don’t correlate to physical reality. Most of the specific practices based on these theories don’t work, which is why thousands of years of using these ideas to guide medicine accomplished almost nothing in terms of improving health or fighting disease. The fact that the systems have similar concepts doesn’t make relying on the concepts, or the interventions derived from them, any more effective.

Collective clinical experience over decades-
There is also the clinical experience of veterinary practitioners to consider- thousands of educated veterinary practitioners worldwide prescribe herbal medicines in their work. This has advantages of being in a modern veterinary context. Veterinary practitioners of botanical medicine have written texts and taught other veterinarians to achieve repeatable results within the botanical framework.

Clinical experience is often the basis for treatment decisions in medicine. It is widely recognized in science-based medicine to be a shaky and unreliable foundation for decision-making compared to controlled scientific research, but often we lack research evidence to fully inform all the care we give. Unfortunately, we all tend to rely too much on experience, and it is common for clinicians to continue employing practices that seem effective to them based on their experience even when better scientific evidence has shown them not to work.

As a community, alternative medicine proponents are even less amenable to abandoning disproven methods than the science-based medicine community. The reverence for tradition and the relatively greater lack of research evidence to support alternative practices leads to a greater trust in experience even than conventional clinicians. Certainly, there are individuals who are committed to a rigorously scientific approach to herbal medicine. However, many of the leaders of the ACVBM have repeated expressed the view that science is predominantly a way of proving to others what they already know to be true from their own experience, rather than honestly testing their beliefs. Science does not yet support the claim here that herbal practitioners can achieve “repeatable results,” and unfortunately it is unlikely that the leaders of this group will change their minds and give up practices they believe to be effective even if good research evidence shows this.

The available published literature on phytochemistry and preclinical pharmacology (that frequently involve animal models exploiting mice, rats, rabbits and less so cats and dogs) of plant extracts is prolific. There are peer-reviewed journals devoted to the subject. Researchers have no doubt that nature is still the preeminent synthetic chemist and that in plants there are infinite reserves of fascinating constituents with actual and potential effects on health and disease. As such information accumulates it is often easier to better understand traditional uses of plants.

They do not however provide confirmation of a clinical effect; experience in practice is that the effect of the whole plant is rarely predicated on the effects of its parts. However such studies help to provide a rationale for the mechanisms of action of a herb.

For once, I agree completely. The bulk of research evidence concerning plant compounds is pre-clinical basic lab research. There is a lot that suggests these compounds may have significant medical value when used in the right way for the right problems. However, this kind of research does not justify the extensive use of herbal remedies in actual patients, which is precisely what the ACVBM is not only recommending but suggesting should be viewed as a legitimate medical specialty.

There are few well conducted placebo controlled double blind clinical trials on the effects of herbs in veterinary medicine. These are expensive to conduct and present methodological and logistical challenges. However, the evidence is accumulating in human medicine and rising in veterinary medicine.

Again, first half true, second half merely opinion. The overwhelming majority of the medical use of herbs in humans has not been proven in clinical trials to be safe or effective. Even some of the most widely used and promising herbal interventions that have been studied for decades, such as St. John’s Wort, have failed to show benefits that outweigh the risks. There is no repeatable, high-quality clinical trial evidence for any herbal prescribing in veterinary species. Such research must be conducted before we can even know if herbal medicine is useful, much less before we can call it a medical specialty.

No single source can absolutely confirm that herbs are a rational treatment strategy.Therefore, it is appreciated that herbs have been dismissed by many in the profession as the refuge of the uncritical. However, when all the sources of information come together and are integrated with pharmacological insights, something important happens; unique treatment strategies for treating notoriously difficult clinical problems become possible and the desire of the ACVBM is for animals to benefit from the efforts of this group to further develop the field.

Pure faith here. All of the evidence sources taken together suggest that some herbal products might be useful for some conditions in some cases, and these are worth testing. Nothing here shows convincingly that any herbal practice is dramatically effective or that herbal medicine has advanced to the point where it should be a medical specialty on a par with oncology, internal medicine, or other specialty areas in which the level of research evidence is dramatically higher.

The section on “philosophy” is especially interesting. A number of elements have been omitted, including the notion of non-physical spiritual or “energetic” forces involved in health and disease, which many of the leaders of the ACVBM have promoted elsewhere as integral to their practice. However, this section still shows some of the beliefs and assumptions behind herbalism which are problematic from the point of view of science.

The universal role of plants in the treatment of disease is exemplified by their use in all the major systems of traditional medicine and ethnomedicine irrespective of their underlying philosophical premise.

This may or may not be true, but it is irrelevant and an example of the appeal to popularity fallacy. Because something is widely practiced or believed has no bearing on whether it is true or should be accepted or adopted. The majority of pre-scientific folk medicine traditions also include specific religious or spiritual beliefs and practices, but that doesn’t mean these should be incorporated into science-based veterinary medicine.

The practitioner of botanical medicine regards the whole formula or whole extract as the “active ”component” in the therapeutic context.

The concept of polyvalent or multifaceted activity of the medicine is central to botanical medicine
-in the context of the advantage of chemical complexity -and even a single herbal extract is a natural multi agent medicine that can simultaneously target a range of desirable pharmacological effects.

The veterinary botanical practitioner prefers not just to prescribe chemically complex herbs, but often administers them in complex formulations, compared to conventional medicine preferring to prescribe a single drug. The practitioner chooses herbs or formulas for a cooperative or facilitating effect between the components to address therapeutic goals

Again, we see the commitment to the idea that plant chemicals are “natural” and that they are safer or more effective the more are mixed together in an herbal treatment, There is no compelling evidence for this belief, and it is contrary to much of the science of pharmacology that has led to so many medicine far more effective than any pre-scientific herbal treatment. There is a reason we take aspirin instead of chewing willow bark- the results is more predictable and effective. While there may be some combinations of herbal ingredients that work better or have fewer side effects when given together, this has to be proven for each by rigorous science, not simply accepted as fact based on traditional beliefs and unscientific theories.

Philosophically the veterinary botanical medicine practitioner practices conventional medicine but overlays that practice with the use of botanical medicines in a framework of botanical principles to expand their options for treatment of disease and optimizing health.

This is the standard claim of integrative medicine. It has a number of problems, which I’ve discussed in detail many times before. Basically, the addition of unproven or ineffective treatments to conventional scientific medicine doesn’t add value for the patient. Adding herbal medicine to conventional treatment will only help patients if those herbal treatments are shown to work. And any particular treatment that works should simply be part of medicine as a whole, not a separate category of “integrative medicine.”

If one is going to use alternative therapies, it is at least better not to use them as replacements for science-based medicine. However, even when practitioners of such therapies say this is what they do, there is reason to be skeptical. The same individuals often promote their treatments as safer and more effective than conventional medicine. If they believe this, wouldn’t they reach for these treatments first? Wouldn’t they likely tell their clients that their herbal treatments are better and safer, which would likely discourage these clients from pursuing conventional care? If they practice Chinese Medicine, as most of the members of the ACVBM leadership do, aren’t they going to evaluate patients and assign treatments based on the principles of this system? Since this is unscientific folk medicine, how is it compatible with a scientific approach to healthcare? The apparently simple claim that herbs aren’t meant to replace conventional treatment raises a lot of questions.

Practitioners appreciate traditional knowledge as just one potential source of information, when coupled with published research and clinical experience, herbs can be prescribed safely and effectively.

Of course, they recognize traditional folk knowledge as a reliable and important source of information, equal if not superior to scientific information about herbal remedies. This is a major danger of validating this approach as a specialty. It treats folk tradition as reliable knowledge, not merely speculations and beliefs that might or might not lead to useful insights and treatments. This attitude erodes the reliance on science that has supported all the tremendous progress in healthcare in the last 150 years and which has made us healthier that all the folk medicine of the preceding millennia.

The ACVBM also makes claims about the scientific basis of herbal medicine. I addressed some of these previously, and the updates to the application don’t add much to the previous discussion.

The ACVBM acknowledges the concerns regarding the scientific basis of veterinary botanical medicine. Where there are published scientific and clinical data supporting the overall safety and benefits of many plant medicines, the research might be dismissed as having methodological bias thus being of inferior quality to trials conducted on conventional drugs.

More accurately, the bulk of research on herbal treatments is pre-clinical, not evaluation of specific treatment approaches in specific groups of patients. The clinical research that does exist is methodologically weak and subject to bias compared with the research literature for conventional medicine. Therefore, very few of the day-to-day practices of herbal veterinarians are based on good science compared to those of conventional practitioners. This needs to be remedied before we can call herbal medicine a specialty.

However to be fair, this is also the case for clinical trials generally. for example in dogs and cats a review of  clinical trials uncovered a need for more high-quality studies. And more recently a cross sectional study of veterinary randomised controlled trials of pharmaceutical interventions funded by different sources was examined and it was found that a failure to report primary outcomes, justify sample sizes and the reporting of multiple outcome measures was a common feature in all of the clinical trials. The authors suggested that findings may be affected by the source of the funding and that some RCT’s provide a weak evidence base and targeted strategies are needed to improve the quality of veterinary RTCs to ensure there is reliable evidence on which to base clinical decisions.

The evidence base for conventional veterinary medicine is far weaker and more limited than it should be. It is also far stronger than the evidence base for veterinary herbalism. And the limitations in the former don’t erase or mitigate the limitations in the latter. The focus should be on building better evidence, not on designating some of the least evidence-based practices as a board-certified specialty.

By increasing awareness, the ACVBM will help the profession as a whole practice botanical EBM. Evidence based medicine however includes not just research, but also incorporates the needs and biases of the client and patient; and the clinical experience of the practitioner; in veterinary botanical medicine this last item has been developed without official support from the veterinary profession and its regulatory bodies, yet is essential to safe and effective practice.

This is a bit of a mischaracterization of evidence-based medicine. It is a system for recognizing the strengths and weaknesses of different kinds of evidence and for making the integration of scientific research evidence into daily practice explicit and formal. Clinical experience is acknowledged as both indispensable and highly unreliable as a guide to the safety and efficacy of treatments.

The ACVBM generally privileges tradition and experience over scientific evidence by claiming that herbal therapies can be broadly described as safe and effective and worthy of specialty status in the absence of any robust body of clinical research literature. The very act of seeking specialty recognition first and then promising to do the research later shows the lack of understanding that such research is not just nice to have but a necessity if we are to have any real confidence in our treatments.

If the ACVBM wishes to advance EBM and make the profession as a whole more evidence based, they would do better to form and fund a vigorous research community doing high-quality research to validate their core beliefs (such as the superiority of whole-plant remedies and mixtures over isolated compounds) and the clinical effectiveness of their treatments. Once a strong body of evidence is available, integration of such methods and recognition as a specialty would make sense.

Bottom Line
There are some positive changes in this updated application. It is clearly an attempt to allay concerns expressed about the lack of evidence for herbal treatments, the reliance on folk wisdom and tradition to guide herbalism, and the lack of a good foundation for treating herbalism as a medical specialty rather than simply evaluating and using herbal remedies scientifically within the existing framework of science-based medicine.

However, the changes to the document do not alter the fundamental objections I raised at the beginning of this post. Ultimately, there is not yet sufficient scientific evidence to validate most of the claims made for herbal remedies. The ACVBM leadership consists predominantly of individuals who espouse unscientific approaches to health and diseases, such as Chinese Medicine, and who have demonstrated the belief that science serves not to test the truth of their beliefs but to aid in marketing them to the rest of the profession.

The best thing this group could do, for herbal medicine and for veterinary medicine as a whole, would be to stop seeking recognition and formal acceptance of their existing practices and beliefs but instead to commit to a rigorous and objective scientific evaluation of those beliefs and practices. The talent and resources spent lobbying and promoting herbalism would be far more valuable if used to test herbal treatments in objective, unbiased scientific studies. If they don’t work, then we’ll know and we can move on. If they do work, then we’ll know and we can make use of them. Either way, veterinary medicine and our patients will benefit. Recognizing unproven folk beliefs and practices as a medical specialty will not advance veterinary medicine or benefit our patients.

Posted in Herbs and Supplements | 5 Comments

British Veterinary Body (RCVS) Accepts the Reality about Homeopathy that AVMA Couldn’t- It’s Nonsense!

Regular readers night remember a few years back when I was involved in promoting a non-binding policy statement from the American Veterinary Medical Association (AVMA) that would have acknowledged a simple and obvious principle: Vets should base their treatments on science and shouldn’t use ineffective, unscientific methods. Here is the text of that statement:

RESOLVED, that the American Veterinary Medical Association (AVMA) affirms that—

1. Safety and efficacy of veterinary therapies should be determined by scientific investigation.

2. When sound and widely accepted scientific evidence demonstrates a given practice as ineffective or that it poses risks greater than its possible benefits, such ineffective or unsafe philosophies and therapies should be discarded.

3. In keeping with AVMA policy on Complementary and Alternative Veterinary Medicine, AVMA discourages the use of therapies identified as unsafe or ineffective, and encourages the use of the therapies based upon sound, accepted principles of science and veterinary medicine.

4. Homeopathy has been conclusively demonstrated to be ineffective.

This resolution was based on a policy already adopted by the Australian Veterinary Association (AVA) and was consistent with the policies of other veterinary organizations, such as the British Small Animal Veterinary Association (BSAVA) Similar positions have been taken by numerous scientific and government bodies around the world (e.g. UK House of Commons Science and Technology Committee and National Health Service, the Australian National Health and Medical Research Council, the U.S. Federal Trade Commission, the European Academies Science Advisory Council, and others).

I wrote a white paper exhaustively detailing the evidence against homeopathy and demonstrated why the evidence presented in favor of the practice was not reliable. The AVMA’s own scientific body, the Council on Research, agreed there is no evidence to support the use of homeopathy. Nevertheless, the resolution was defeated by a 9:1 margin, illustrating the definitive preference for political expediency over science in AVMA policy.

Now, the status of the AVMA as an outlier for refusing to acknowledge the obvious truth that homeopathy is a worthless set of false beliefs and ineffective methods is further emphasized by a recent revision to the policy on complementary and alternative medicine byt the council of the Royal College of Veterinary Surgeons (RCVS), the regulatory body for veterinarians in the UK. Similar to the AVA policy and the resolution rejected by the AVMA, the policy reads as follows:

We have recently been asked questions about complementary and alternative medicines and treatments in general and homeopathy in particular. We would like to highlight our commitment to promoting the advancement of veterinary medicine upon sound scientific principles and to re-iterate the fundamental obligation upon our members as practitioners within a science-based profession which is to make animal welfare their first consideration.

In fulfilling this obligation, we expect that treatments offered by veterinary surgeons are underpinned by a recognised evidence base or sound scientific principles. Veterinary surgeons should not make unproven claims about any treatments, including prophylactic treatments.

Homeopathy exists without a recognised body of evidence for its use. Furthermore, it is not based on sound scientific principles. In order to protect animal welfare, we regard such treatments as being complementary rather than alternative to treatments for which there is a recognised evidence base or which are based in sound scientific principles. It is vital to protect the welfare of animals committed to the care of the veterinary profession and the public’s confidence in the profession that any treatments not underpinned by a recognised evidence base or sound scientific principles do not delay or replace those that do.

While there is some contortion of reasoning evident here to allow merely discouraging the replacement of real medicine with homeopathy, rather than actively opposing the use of homeopathy altogether, which is a concession to the political reality that some vets still employ it regardless of the lack of any reasonable basis for doing so, this is still a strong statement that veterinary medicine should be based in science and that homeopathy is not a scientifically legitimate practice. It is an important step forward in leaving behind faith-based folk medicine and emphasizing the importance of a science-based practice to the welfare of veterinary patients.

The growing chorus of organizations in medicine and government around the world rejecting homeopathy is in contrast to the depressing inability of organized veterinary medicine here in the U.S. to take such a simple, obviously correct stand in favor of what is ultimately best for our patients. We should be leading, and instead we are dragging our heels as the future of medicine, including veterinary medicine, continues moving towards scientific, evidence-based practices and away from the relics of pre-scientific folk medicine. Here in the US, one can argue that Chinese medicine, homeopathy, chiropractic, and other unscientific approaches may even be gaining ground despite their consistent failure to prove their worth. This is an unfortunate state fo affairs for our profession and our patients.

I am happy that the RCVS council has taken this step towards protecting the welfare of veterinary patients and the rights of animal owners in the UK to truly informed consent. I can only hope that we in the US will eventually overcome our resistance to any constraints on the autonomy of individual veterinarians and recognize that similar policies will serve the veterinary profession and the welfare of our patients far better than the current refusal to stand up against the anti-scientific nonsense of veterinary homeopaths and other purveyors of unscientific treatments and folk medicine. We owe this to the animals in our care and to our clients.

Posted in Homeopathy, Law, Regulation, and Politics | Leave a comment

Alternative Medicine Kills Cancer Patients

One of the most dangerous aspects of unproven or ineffective alternative therapies is the harm to patients when these are used in place of scientific medicine. While most proponents of alternative therapies generally recommend them as an addition to conventional treatment, despite the lack of evidence this improves care, some advocates of alternative medicine condemn conventional therapies and claim unproven alternatives are as good or better. This is especially common in relation to cancer treatment. Promoters of alternative medicine often very aggressively criticize or deride conventional cancer treatments as harmful and ineffective. A new study adds to existing evidence that turning to alternative treatments for cancer is a very dangerous choice.

Skyler B. Johnson, Henry S. Park, Cary P. Gross, James B. Yu; Use of Alternative Medicine for Cancer and Its Impact on SurvivalJNCI: Journal of the National Cancer Institute, Volume 110, Issue 1, 1 January 2018.

This study looked at human patients with a variety of cancers who chose to use various alternative treatments instead of conventional treatment. The patients were representative of the demographic characteristics typically associated with alternative medicine users: predominantly white, female, affluent, and educated. After controlling for other variables, alternative medicine use was associated with markedly lower survival times for every cancer evaluated except for prostate cancer, which tends to be very slowly progressive and much less likely to lead to mortality than most of the other cancers evaluated. The authors’ conclusions are quite clear:

we found that cancer patients who initially chose treatment with AM without CCT were more likely to die. Improved communication between patients and caregivers and greater scrutiny of the use of AM for the initial treatment of cancer is needed.

Of course, many advocates of alternative therapies will claim that this study doesn’t address the value of such treatments added to conventional medicine. However, it isn’t at all clear why therapies that evidently don’t work by themselves would add value when mixed with conventional treatments. And in any case, there isn’t yet any compelling evidence to support the integration of alternative cancer therapies with scientific medicine, and plenty of reasons to be skeptical of it. But this study reinforces existing evidence that turning to alternative medicine instead of scientific medicine when you have cancer is a potentially deadly choice.




Posted in General | 4 Comments

European Scientists Join Chorus of Government and Scientific Organizations Acknowledging the uselessness of Homeopathy

The evidence that homeopathy is ineffective for any and all medical problems and is nothing more than a placebo has grown steadily for over a century. Many reviews of the scientific research have been done, and despite hundreds of studies, no reliable evidence exists to support the core principles of homeopathy or the actual real-world benefits claimed by its practitioners. I reviewed this evidence in detail in support of a resolution before the American Veterinary Medical Association (AVMA) to declare homeopathy ineffective and discourage its use in veterinary patients. I also exhaustively examined the evidence provided in support of homeopathy and discussed why it is unreliable and unconvincing. The AVMA’s scientific advisory body, the Council on Research, agreed that “that there is no clinical evidence to support the use of homeopathic remedies for treatment or prevention of diseases in domestic animals.” Unfortunately, politics won out over truth, and the AVMA refused to acknowledge the obvious—that homeopathy is useless and veterinarians promoting it are deceiving animal owners.

Several scientific bodies around the world have reviewed the same evidence and come to the same conclusion. The United Kingdom House of Commons Science and Technology Committee conducted hearings and a thorough evidence review and came to stark and clear conclusions:

In our view, the systematic reviews and meta-analyses conclusively demonstrate that homeopathic products perform no better than placebos.

There has been enough testing of homeopathy and plenty of evidence showing that it is not efficacious. Competition for research funding is fierce and we cannot see how further research on the efficacy of homeopathy is justified in the face of competing priorities.

For patient choice to be real choice, patients must be adequately informed to understand the implications of treatments. For homeopathy this would certainly require an explanation that homeopathy is a placebo. When this is not done, patient choice is meaningless. When it is done, the effectiveness of the placebo—that is, homeopathy—may be diminished.

We recommend that the MHRA remove all references to homeopathic provings from its guidance other than to make it clear that they are not evidence of efficacy.

We consider that the way to deal with the sale of homeopathic products is to remove any medical claim and any implied endorsement of efficacy by the MHRA—other than where its evidential standards used to assess conventional medicines have been met—and for the labelling to make it explicit that there is no scientific evidence that homeopathic products work beyond the placebo effect.

It is unacceptable for the MHRA to license placebo products—in this case sugar pills—conferring upon them some of the status of medicines. Even if medical claims on labels are prohibited, the MHRA’s licensing itself lends direct credibility to a product. Licensing paves the way for retail in pharmacies and consequently the patient’s view of the credibility of homeopathy may be further enhanced. We conclude that it is time to break this chain and, as the licensing regimes operated by the MHRA fail the Evidence Check, the MHRA should withdraw its discrete licensing schemes for homeopathic products.

By providing homeopathy on the NHS and allowing MHRA licensing of products which subsequently appear on pharmacy shelves, the Government runs the risk of endorsing homeopathy as an efficacious system of medicine. To maintain patient trust, choice and safety, the Government should not endorse the use of placebo treatments, including homeopathy. Homeopathy should not be funded on the NHS and the MHRA should stop licensing homeopathic products.

Despite significant political resistance, including from members of the royal family, this message has been heard, and homeopathy has been banned from government-provided healthcare in the UK.

The government of Australia conducted a similar, exhaustive review over several years, with plenty of opportunity for input from supporters of homeopathy. This review also agreed with those that went before, concluding:

Based on all the evidence considered, there were no health conditions for which there was reliable evidence that homeopathy was effective. No good-quality, well-designed studies with enough participants for a meaningful result reported either that homeopathy caused greater health improvements than placebo, or caused health improvements equal to those of another treatment.

NHMRC concludes that there are no health conditions for which there is reliable evidence that homeopathy is effective. Homeopathy should not be used to treat health conditions that are chronic, serious, or could become serious. People who choose homeopathy may put their health at risk if they reject or delay treatments for which there is good evidence for safety and effectiveness.

Historically, the U.S. is less amenable to government regulation of health care than other developed countries. Homeopathy was grandfathered in to the FDA regulatory system by politicians in the 1930s, and since then there has been little political will to challenge the practice despite the powerful evidence against it. In 2016, however, both the Federal Trade Commission (FTC) and the FDA conducted reviews, with public comment, regarding their oversight of homeopathy. No report or action has yet resulted from the FDA review, and given the anti-science and anti-regulatory views of the current administration, it seems unlikely this will change any time soon. However, the FTC, which regulated advertising of healthcare products, did come out with a strong pro-science position on homeopathy last year:

For the vast majority of OTC homeopathic drugs, the case for efficacy is based solely on traditional homeopathic theories and there are no valid studies using current scientific methods showing the product’s efficacy.  Accordingly, marketing claims that such homeopathic products have a therapeutic effect lack a reasonable basis and are likely misleading in violation of Sections 5 and 12 of the FTC Act.

Nevertheless, truthful, nonmisleading, effective disclosure of the basis for an efficacy claim may be possible.  The approach outlined in this Policy Statement is therefore consistent with the First Amendment, and neither limits consumer access to OTC homeopathic products nor conflicts with the FDA’s regulatory scheme.  It would allow a marketer to include an indication for use that is not supported by scientific evidence so long as the marketer…effectively communicates to consumers that (1) there is no scientific evidence that the product works and (2) the product’s claims are based only on theories of homeopathy from the 1700s that are not accepted by most modern medical experts.

Essentially, what the FTC has said is that one can claim homeopathy works only if one admits that there is no scientific evidence for this claim and that it is based on pre-scientific folk beliefs with no validity.

The most recent addition to this chorus of official voices acknowledging the lack of benefit to homeopathy is the European Academies Science Advisory Council (EASAC), which recently issued a strong statement warning of the misleading nature of claims for homeopathy.

EASAC, the European Academies Science Advisory Council, is publishing the present Statement to reinforce and reiterate this extensive and well-founded critique and to encourage and support (i) policy makers in the EU in taking a more explicitly evidence-based approach to assessing the claims for homeopathy and (ii) all those interested in stimulating better public engagement with these contentious issues and in improving consumer’s rights to correct information.

…there is no robust, reproducible evidence that homeopathic products are effective for any known diseases, even if there is sometimes a placebo effect. Moreover, homeopathy can actually be harmful: by delaying or deterring a patient from seeking appropriate, evidence-based, medical attention and by undermining patient and public confidence in scientific evidence.

From analysis of the appropriately controlled, verifiable evidence base, any claimed efficacy of homeopathic products in clinical use can be explained by the placebo effect or attributed to poor study design, random variation, regression towards the mean, or publication bias…The scientific claims made for homeopathy are implausible and inconsistent with established concepts from chemistry and physics.

The promotion and use of homeopathic products risks significant harms as mentioned above. In addition, homeopathy raises issues of concern for patient informed consent if health practitioners recommend products which they know are biologically ineffective. There are also potential safety concerns for homeopathic preparations because of poorly monitored production methods.

  • There should be a consistent regulatory requirement for claims for the efficacy, safety and quality of all medicinal products to be based on verifiable and objective evidence, commensurate with the claims being made. The necessity for robust data applies to products for both human and veterinary medicine.

  • Public health system budgets are under increasing pressure. Evidence-based public health systems should not offer reimbursement for homeopathic products and services unless they are demonstrated to be efficacious and safe by rigorous testing.

The growing willingness of scientists, individually and through their organizations, and of regulatory bodies to confront pseudoscience and unscientific nonsense like homeopathy is an encouraging sing, and it is beginning to have an impact, as seen in the withdrawal of NHS support for homeopathic treatment. Ultimately, the more willing we in science are to challenge unscientific claims and methods and to take the time to explain the evidence to people, the more the public will be able to make sound, fully informed healthcare choices, which is what this blog is all about.

Posted in Homeopathy | 3 Comments

American Animal Hospital Association (AAHA) 2017 Canine Vaccination Guidelines

In previous discussions of vaccination recommendations, I have referenced several clinical guidelines that review the existing evidence and provide recommendations for vaccination. The American Animal Hospital Association (AAHA) and American Association of Feline Practitioners (AAFP) guidelines are quite extensive and useful documents in making decisions about vaccination. AAHA guidelines are, unfortunately, usually prepared by small groups of experts with little transparency, and they are not always a model of evidence-based guideline development (for a great model, see the RECOVER guidelines for small animal CPR). That said, the vaccination guidelines do a good job of summarizing the complex and sometimes contradictory evidence and making reasonable recommendations.

AAHA has update the canine vaccination guidelines, and has presented them in a new form. The 2017 AAHA Canine Vaccination Guidelines are now primarily an online document divided into sections that make finding the answer to specific vaccination questions quite easy. In terms of providing a summary of existing vaccine science and giving a general overview of the issues, the web-based format is clunky and harder to use than a traditional journal article. But in terms of giving direct answers to questions vets and dog owners typically have about when and how to use specific vaccines, the format works well.

The new guidelines also add detail to subjects only lightly discussed in the previous version, including the use of antibody titers to guide vaccination and how to handle animals with uncertain vaccine histories or overdue for boosters of vaccines given previously.

There is nothing revolutionary or earth-shattering in the new guidelines, and they will undoubtedly not satisfy the concerns of those with deep anxieties or objections to routine vaccination practices. The recommendations are very similar to previous versions, and there will be few changes for those of us who have been following these guidelines in the past. Thorny questions like how often, or if, boosters of core vaccines should be given are not always directly answered.

The previous guidelines summarized the evidence that, for example, vaccination for canine parvovirus (CPV) and canine distemper (CDV) should provide immunity for a minimum of three years and likely protects most dogs for at least 5-7 years and possibly longer (when given properly as a series to puppies with a booster at about one year). The currently guidelines recommend intervals for these vaccines of “three years or longer”, which leaves the exact interval to the discretion of vets in practice. This makes sense in many ways, since the risks and benefits of vaccination for individual animals depends on exposure risk, lifestyle, health, medical treatment, and many other variables. Ultimately, there is no single right answer for every dog.

Unfortunately, it is easier for most vets to choose an arbitrary recommendation to make for all their patients. Right now, many choose three year intervals for these vaccinations because that number was specifically suggested in the AAHA guidelines. When I have suggested longer intervals might be appropriate, many of my colleagues are understandably wary of deviating from what all the major veterinary schools and most other practices are doing for fear of being blamed for any failure of protection that might occur. And, of course, none of this will satisfy those who think little or no vaccination is necessary at all.

Despite the inevitable compromises and limitations in the evidence, however, the AAHA guidelines are an excellent resource for vets and dog owners wishing to make rational, science-based decisions about how best to protect dogs from vaccine-preventable disease.

Posted in Science-Based Veterinary Medicine, Vaccines | 30 Comments

Pets deserve Evidence-based Medicine Too!

Here’s a recent interview I did for NPR on the SkeptVet Blog and the need for skeptical, evidence-based medicine for our animal companions.

Why does the world need skeptical veterinarians?

Pet owners need to know the pros and cons of health care options for their pets to make good decisions. “Skeptic” doesn’t mean someone who automatically rejects new or unfamiliar ideas. It’s someone who refrains from judging a claim until they have examined the evidence dispassionately — someone who gives preference to scientific evidence over personal experience, anecdote, tradition or history.

Posted in Presentations, Lectures, Publications & Interviews | 16 Comments