New Review Reminds us Doctors are Lousy at Predicting Benefits and Harms of their Tests and Treatments

One of the major focuses of my criticism of both science-based and alternative medicine is the failure of doctors to recognize their own limitations. There are innumerable cognitive biases and other sources of error that interfere with accurate and effective clinical decision-making. And there are many reasons why uncontrolled observations, whether by doctors or anyone else, are unreliable and inferior to controlled scientific research when trying to understand the causes of disease and the effects of healthcare treatments. The problems caused by opinion-based and faith-based medicine, including the issue of overdiagnosis and overtreatment in mainstream medicine and the persistence of ineffective treatments, especially in alternative medicine, are directly related to our tendency as individuals to trust our own judgment and beliefs far beyond their real reliability.

A new review of studies involving medical doctors illustrates this problem, and reminds us why we have to rely more on science and less on our own opinions and beliefs if we want to provide the best care for our pets and patients.

Hoffmann TC, Del Mar C. Clinicians’ Expectations of the Benefits and Harms of Treatments, Screening, and Tests: A Systematic ReviewJAMA Intern Med. Published online January 09, 2017. doi:10.1001/jamainternmed.2016.8254

This review looked at studies evaluating how well MDs did at predicting the likely benefit or harm to patients of tests and treatments compared with controlled research. The findings starkly illustrated that, “clinicians rarely had accurate expectations of benefits or harms of the interventions, with inaccuracies in both directions, although they more often overestimated rather than underestimated benefits and underestimated rather than overestimated harms.”

The magnitude of this effect was impressive.

Among the studies comparing benefit expectations…most participants provided correct estimation for only 3 outcomes (11%). Of the studies comparing expectations of harm …a majority of participants correctly estimated harm for 9 outcomes (13%). Where overestimation or underestimation data were provided, most participants overestimated benefit for 7 (32%) and underestimated benefit for 2 (9%) of the 22 outcomes, and underestimated harm for 20 (34%) and overestimated harm for 3 (5%) of the 58 outcomes.

Guessing the correct benefit or risk less than 15% of the time and overestimating benefits by 32% and underestimating harm by 34% is a recipe for ineffective, even dangerous care. Though this is a study of MDs, there is no reason to think vets would do any better, and in fact it is likely that vets would perform worse than MDs and alternative medicine practitioners would do worse than those practicing science-based medicine. Vets generally have less pressure to know and conform to evidence-based standards than MDs due to less regulation and litigation. And alternative practitioners are, at best, often uninterested in scientific evidence and sometimes actively hostile to it.

The direction of the effect was also interesting, and consistent with what we know about how the human mind works. As doctors, we overestimate the benefits of our actions and underestimate the risks because we feel pressure to act and to fix things and because we need to believe we are helping our patients effectively. We are quite worried about causing harm, but we also worry more about the risks of not acting than of taking action.

The finding of more instances of clinicians underestimating harms and overestimating benefits than the opposite provides some support for the existence of therapeutic illusion (“an unjustified enthusiasm for treatment on the part of both doctors and patients,” which is a proposed contributor to the inappropriate use of interventions. Other potential contributors include the often-misleading portrayal of intervention benefits and absence of harms data in journal articles and information from commercial sources, such as pharmaceutical advertisements in medical journals.

We found much more focus on assessing expectations about harm than benefit (67% of studies measured harm expectations only) in contrast to our review5 of patient expectations where most studies (63%) focused on benefit expectations. Clinicians may be more sensitive to harming patients rather than just not providing benefit, which may stem from a fundamental concern of primum non nocere: the primary duty of doing no harm. Medicolegal concerns may also influence clinicians to place greater emphasis on the risks of not doing something rather than the risk of harm from intervening.

The response to this kind of information is not, of course, to give up on medicine. Medical care is tremendously effective at reducing suffering and death. The takeaway message is that individual observation and judgment should always be supported and informed by scientific research, which does a better job at evaluating the causes of disease and the effects of treatments than our ad hoc observations.

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New York and FTC Tired of Prevagen False Claims (which are the same as for the veterinary version, Neutricks)

I have written several times about Neutricks, a supplements marketed for cognitive dysfunction in dogs:

Neutricks: Another Nutraceutical for Canine Cognitive Dysfunction

Evidence Update:  Old Tricks Used to Massage Neutricks Study Data

Evidence Update: Neutricks Still up to Same Old Tricks

This supplement has become the paragon of snake oil supplements for its dramatic claims supported by anecdote and shoddy science. The company and its founders have been warned by regulators about their blithe disregard for unsupported claims about the product, and now the Attorney General of New York and the Federal Trade Commission (FTC) have filed a lawsuit to stop the fraudulent marketing of the human version of this product, Prevagen.

Such vigorous action is rare in the current anti-regulatory climate, and it is encouraging to see an effort like this to protect consumers from false advertising, even if it currently is only aimed at consumers of the human version of the product. The New York AG was quite blunt in describing the suit:

“The marketing for Prevagen is a clear-cut fraud, from the label on the bottle to the ads airing across the country,” the New York Attorney General Eric Schneiderman said in a statement. “It’s particularly unacceptable that this company has targeted vulnerable citizens like seniors in its advertising for a product that costs more than a week’s groceries, but provides none of the health benefits that it claims.”

The FTC was equally direct:

According to the FTC, the makers of Prevagen relied on a single study to back up their false claims. And the study didn’t even show that Prevagen improved memory better than a placebo. To make matters worse, the FTC and New York Attorney General allege that the company behind Prevagen was actively targeting seniors who were struggling with deteriorating memory.

“The marketers of Prevagen preyed on the fears of older consumers experiencing age-related memory loss,” Jessica Rich, director of the FTC’s Bureau of Consumer Protection, said in a statement. “But one critical thing these marketers forgot is that their claims need to be backed up by real scientific evidence.”

Even in this supposed “post-fact” era, it is good to see that at least some in government recognize the need for real scientific evidence for healthcare products to protect consumers from snake oils like this. Hopefully, if this suit is successful, the same principles of consumer protection and scientific will be applied to the veterinary market and pet owners, though sadly standards are often lower for pet products.

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Pet Remedy- A “Natural” Herbal Product to Reduce Stress and Anxiety

There are an enormous number of unregulated over-the-counter remedies marketed to pet owners, often for serious health problems, and most of them have never been scientifically tested to see if they are safe or effective. It is difficult to evaluate these products objectively when there is no real evidence. There are always, of course, plenty of anecdotes and testimonials, but while people frequently find these persuasive, I have explained many times in detail why they do not actually tell us much at all about the safety or effectiveness of such products.

Often, the best pet owners and veterinarians can do is consider whether the claims made for such products are reasonable or fanciful, whether the theoretical justifications for how they might work make sense or not, and whether there is any obvious danger. This is not a very reliable or satisfactory way to evaluate healthcare products, but in the absence of regulatory requirements to prove any claims manufacturers make or any ethical commitment on the part of these manufacturers to back up their own claims, this is sometimes the best we can do.

Even when there is some research on a product, however, often the evidence is of limited reliability. And of course, companies never accept any negative reports on their products, and they tend to exaggerate or even mislead consumers regarding the strength of the evidence for their products. I recently ran across a nice study on an herbal product called Pet Remedy, which led me to look at the company marketing materials. Not surprisingly, the marketing does not reflect the evidence for this product.

What Is It?
Pet Remedy is a mixture of several plant extracts. According to the manufacturer, these include extracts from valerian root, vetiver, sweet basil, and Spanish sage. The exact amount of these ingredients, unfortunately, is not disclosed, though the company indicates the valerian content is “very low,” suggesting enough to have the purported benefits of relaxation without the potential. The product comes in a variety of forms, including sprays and plug-in diffusers. The advertising material provides this information about the development of Pet Remedy:

Developed as a result of one of our directors having a cat with behavioural issues! Pet Remedy sorted the problem so effectively that Pet Remedy was then created as a marketable product with a range of plug diffuser, calming sprays, and battery operated atomiser. Pet Remedy was developed with the help of a team comprising several vets, nurses, a psychiatrist and using our own experience in the aromatherapy and essential oil markets.

The company makes broad and sweeping claims for it including:

Clinically proven to calm pets without sedating

Pet Remedy is 100% safe for all mammals and birds, including dogs, cats, rabbits, guinea pigs, hamsters, parrots and horses.

Regular readers will be familiar with my views on claims of significant benefits with absolutely no risk, which I have codified into McKenzie’s Law:

The company quite explicitly claims scientific support for their product. They propose a mechanism of action based on previous studies of valerian extracts:

…the active ingredients in the special Pet Remedy blend will sit on the cell receptor as if a GABA molecule was sitting on it, and that activates (excites) the receptor into giving the cell the message to calm.

The other ingredients are presented in terms of their traditional use, with a lot of vacuous language and extravagant claims that sound like they were copied out of herbal medicine books:

This plant has been appreciated for its calming properties since records began.

Basil oil is a good tonic for the treatment of nervous disorders and stress related headaches, migraines and allergies. It is used to clear the mind and relieve intellectual fatigue, while giving clarity and mental strength.

The therapeutic properties of sage oil are anti-inflammatory, antibacterial, antiseptic, antispasmodic, astringent, digestive, diuretic, emmenagogue, febrifuge, and hypertensive,.There also seems to be a more general relaxant effect, so that the plant is suitable in the treatment of nervousness and excitability. It helps to fortify a generally debilitated nervous system.

The company is also quite specific about the strength of the purported scientific evidence behind their product:

We have already conducted three major clinical Trials…The results of all trials are consistent with pet remedy being an effective natural aid to calm stressed pets.

They also list a number of other studies in progress and offer to send copies of the study reports upon request. Needless to say, I sent such a request since I was otherwise only able to find the one study I had initially run across.

Does It Work?
Valerian has been claimed to be useful as a sleep aid and anxiety reducing herb. The evidence for these claims is limited and mixed in humans (e.g. 1, 2), suggesting there may be some benefits but without definitive proof of these. As usual, there is virtually no good scientific research on the use of this herb in veterinary patients. It is plausible that this herb might have some calming effects in the species the company markets it for, but this does not obviate the need for actual clinical studies of the product itself.

The evidence for medicinal uses of vetiver, basil, and Spanish sage in humans is weaker than for valerian, and again there are essentially no controlled clinical studies to support veterinary use.

When I requested copies of the studies the company uses to promote Pet Remedy, I received two unpublished reports from a statistical analysis firm hired to analyze data collected in two studies and also a draft report of the published study I had already seen. Interestingly, the company did not direct me to the published report of this last study, even though that is available freely through the journal. The company representative also sent me the unpublished results of a survey of groomers suggesting that, when asked, many reported they would be willing to recommend the product. This, of course, amounts to no better evidence than the many testimonials and anecdotes available on the company web sites.

The first unpublished study involved 60 dogs receiving behavior modification therapy who were alternately exposed to Pet Remedy or a placebo. The report doesn’t indicate that important controls for bias were included (randomization, blinding, etc.), and it reports vague and subjective outcome measures: “excitement” on a 5-point scale from “not excited” to “very excited” and “behavior” on a similar scale from “poor/unacceptable” to “better/good.” These are certainly not the hallmarks of good-quality behavioral research, which likely explains why the study has not been published.

The company statistician appears to recognize that the design disallows any meaningful conclusions about the efficacy of the product. Despite reporting some differences in the outcome measures for the dogs when exposed to Pet Remedy or placebo, several cautionary statements are included, such as:

It was noted that as no data were available on the baseline (pre-study intervention) behaviour scores and excitement levels for the dogs, it would not be appropriate to compare the August outcomes between the dogs receiving the Pet Remedy and the placebo in the first month. This would fail to take into account the baseline excitement level and behaviour score of the dogs when they entered the study.

It is important to acknowledge that, due to the design of the study, it is not possible to directly attribute the changes observed to the study treatment received in the current month in each case. As each dog was switched between placebo and Pet Remedy from month-to-month, it is not possible to rule out the possibility of so-called carryover or lagged effects of the treatments received in previous months.

It should be reiterated that, due to the design of the study, it is not possible to directly attribute the changes observed in the trial to the study treatment received in the current follow-up month in each case. This is because of the possibility of so-called carryover or lagged effects of the treatments received in previous months.

We would recommend running another study to replicate the effect with a study design that would allow us to determine whether this was indeed due to the study treatment. Select would be more than happy to provide advice on how best to design the study from a statistical point of view.

I was sent another report from the same statistical company that was named as reporting a different study. The date on the report was different, but the content was exactly the same, so I suspect this may have been an error, but I was not able to evaluate the report from this trial. Information from the company web site indicates both trials used the same design and outcome measures, so it seems likely the caveats of the one I was able to review apply to the one I was not, especially given neither have been published.

I was also sent a couple of Excel spreadsheets with data and notes about the subjects in the two studies.  These were surprisingly revealing. In fact, they contain individual identifying information for study subjects and owners, which is typically not supposed to be shared outside of the study team. The study was conducted at a private training facility, not an academic institution, which may explain the failure to follow standard study design or ethics guidelines.

These spreadsheets do seem to confirm the lack of blinding and randomization, and support the subjective nature of assessments and potential for bias. A note from one of the investigators, for example, indicates that dogs in one of the studies who were exposed to Pet Remedy in the first month were switched to placebo in the second month, as per the study design, but that those owners who thought the remedy was helpful the first month and asked to switch back to it were allowed to do so. This would be a pretty serious violation of basic study design procedures.

One of the spreadsheets also contains notes about the prognosis for the dogs. These show that the evaluators make judgements about whether or not the dogs could be helped as part of their initial assessments. Some were described positively (e.g. “this one will be easy to resolve” and “can’t wait to work with this little man.”) and others quite negatively (e.g. “Not all together put together this dog has brain issues… This dog needs to be PTS ASAP he has mental health issues” and “This dog is a menace.”).

A rather large number of these comments, in fact, suggest the dogs are very dangerous or should be euthanized. This both indicates this is not a typical population of dogs whose owners are likely to want an over-the-counter herbal remedy and also that, in the absence of blinding and randomization, there is a significant risk of individual bias in how the dogs and the treatments were evaluated. In any case, neither of these studies has been published or appears to meet the basic criteria for a reliable controlled scientific study.

The final study was the one I originally found published in the journal Animals.

Taylor,  S. Madden, J. The Effect of Pet Remedy on the Behaviour of the Domestic Dog (Canis familiaris) Animals 2016, 6(11), 64; doi:10.3390/ani6110064

The published study had much better methodology than the other two, including appropriate randomization and blinding. It involved exposing 28 dogs (a pretty small number) to either Pet Remedy or a placebo in an unfamiliar and evaluating for behavioral signs of anxiety. Dogs were chosen whose owners had indicated that they showed signs of anxiety or aggression in unfamiliar places. The study concluded that the product had no effect:

In the current study, no statistically significant differences in behaviour were found in either the Pet Remedy or placebo condition. A lack of a discernible effect under either condition suggests that Pet Remedy did not affect behaviour of dogs’ placed in a potentially stressful non-familiar environment.

This is a pretty clearly negative result in a study that did a much better job controlling for bias than the unpublished studies the company publicizes. In fact, I initially thought it pleasantly surprising that the company would direct consumers to scientific evidence that does not support their claims. However, it turns out the company is doing everything it can to present this study as a success despite the lack of any actual effect.

For one thing, the company lists and describes the study on its web page but leaves out the fact that it found no benefit. The site even says say, “The results of all trials are consistent with pet remedy being an effective natural aid to calm stressed pets.” This is clearly not true. The reality is that the two unpublished studies are unreliable and the published study showed no effect.

The misleading attempt to spin weak and even negative evidence even extended to sending me an unpublished preliminary version of the study report that differed from the published version, even though the published paper is freely available. This was done because the preliminary version presents a much more positive interpretation of the data. In the initial version, two of the many outcome measures evaluated were reported as showing a statistical difference between Pet Remedy, and then this was presented as suggestive of a benefit despite the lack of any difference on all the other measures.

Pet Remedy also significantly decreased overall yawning behaviour; indicative of reduced anxiety although overall heart rate did not significantly differ between treatments. Pet Remedy also significantly affected rates of change in locomotory behaviour but not change in heart rate, with activity decreasing more slowly in comparison to a placebo. The results suggest that Pet Remedy may be a useful tool for reducing canine stress and anxiety in dogs that display suppressed behaviour by increasing activity whilst reducing anxious behaviour. Reduced anxiety may also lower the number of dogs being relinquished to shelters as a result of anxiety related behavioural problems. In turn, Pet Remedy may have potential value in enhancing the welfare of these individuals.

The final paper in published form was apparently edited as a result of the peer review, resulting in the removal of these likely spurious findings and a conclusion more clearly reflecting the lack of any real effect in the data.

Is It Safe?
As pointed out already, the claim of 100% safety can only be true if there is no effect at all, since any treatment which has beneficial effects will almost certainly have potential undesirable effects as well.  The company acknowledges that some such effects have been reported with valerian, but of course they claim that their product is perfectly designed to reap the benefits without these side effects:

Many Valerian preparations are too potent and can sedate rather than calm. Pet Remedy is a low concentration valerian blend and the diffuser delivers a constant slow release, which is very kind and gentle in its effect on the metabolism.

No evidence is provided to substantiate this claim.

Given the limited veterinary research available on this product and its ingredients, the question of safety remains unanswered. It seems unlikely that small amounts of these substances volatilized through a diffuser would have serious risk, just as it seems unlikely they would have dramatic benefits, but in the absence of good evidence, we can only speculate.

Bottom Line
Pet Remedy is an example of the tremendous number of herbal products marketed to pet owners with extravagant claims but little real evidence to support these. This company explicitly claims strong scientific support for their dramatic claims of safety and efficacy. However, the evidence consists only of anecdote, poor-quality unpublished studies funded by the company, and one reasonably good published study that shows no effects, despite the company’s attempts to imply otherwise.

Like the purported benefits, the claimed absolute safety of the product is also not supported by good scientific evidence. There is little reason to think it is especially dangerous, just as there is little reason to think it has significant benefits, but the marketing claims for both safety and efficacy are not, as the company claims, supported by good science.

The company claims a number of additional studies are in progress. If these turn out to have appropriate design and execution, they may clarify whether there are any benefits to this product. If, however, the company persists in exaggerating the significance of poor-quality unpublished studies and ignoring negative results from more reliable research, then these additional studies will do nothing but create the false appearance of scientific legitimacy where it does not exist.

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Does Challenging or Ridiculing Crazy Ideas Change Anyone’s Mind?

It has long been a sad and frustrating but generally accepted notion among skeptics that facts don’t matter to people who believe in pseudoscience, conspiracy theories, and other dubious ideas or claims. The so-called “backfire effect” appears to mean that people will only fortify their beliefs if challenged with contradictory facts, so arguing with people only reinforces their beliefs. And it is also widely believed that, as the old saw has it, “You catch more flies with honey than vinegar.” Finding common ground, building trusting relationships, and showing empathy and respect are generally believed to be more conducive to changing someone’s mind than ridicule or hostility.

A recent study appears to challenge these concepts, suggesting that beliefs about conspiracy theorie can be wekaned by both facts and ridicule directed at those beliefs.

Gábor Orosz, Péter Krekó, Benedek Paskuj, et al. Changing Conspiracy Beliefs through Rationality and Ridiculing. Frontiers in Psychology. 2016, Vol 7.

Orac has done a thorough job of summarizing this study, so I will just hit a few highlights. This study exposed subject to unfamiliar conspiracy theories and then to several different attempts to undermine these theories, divided into factual rebuttal, ridicule, and attempting to generate empathy for the “villains” of the conspiracy theory. They then measured several indices of the subjects’ views. The authors concluded that,

Rational and ridiculing arguments were effective in reducing CT [conspiracy theories], whereas empathizing with the targets of CTs had no effect. Individual differences played no role in CT reduction, but the perceived intelligence and competence of the individual who conveyed the CT belief-reduction information contributed to the success of the CT belief reduction. Rational arguments targeting the link between the object of belief and its characteristics appear to be an effective tool in fighting conspiracy theory beliefs…

They also recognized that this conclusion is contrary to established ideas and existing evidence, and so it must itself be treated with a bit of skepticism.

Our findings on the efficiency of rational argumentation go against the mainstream of the communication literature and “common wisdom,” as well as the current affective wave of social psychology emphasizing that emotions constitute the most important factor behind shaping beliefs and attitudes. Considering the modest effect sizes, we assume that rationality has a bigger impact on shaping (sometimes irrational) beliefs than previously expected, given that in the current communication environment, people are overloaded with emotional messages coming from ads, political and social campaigns. Future studies should also investigate the role of rationality and the “rationality heuristic” in belief change.

Orac points out what may be a key aspect of this study. The subjects were not established believers in the conspiracy theories they were exposed to. They were, to relate the study to the issues of this blog, less like homeopaths and more like conventional vets or pet owners with little knowledge and no firm opinions about homeopathy. I have long argued that while battling with true believers accomplishes nothing in terms of changing their minds, playing out such arguments in public may have an influence on the uncommitted majority, who should be the real audience for factual rebuttal and ridicule of unproven and false medical claims. This study provides at least a tiny bit of hope that such an approach may have value.

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Another Systematic Review of Homeopathy and–Wait for It– Still No Good Evidence It Works!

Yet another systematic review of veterinary homeopathy has just been published, bringing the total to six. I have discussed several of these before (e.g. 1, 2). They have consistently failed to find high-quality research evidence to support homeopathy in animals, despite the fact that the previous reviews have been conducted by advocates for homeopathy. Most of the studies identified fail even basic methodological criteria for reliability, and there is a lack of consistency and reproducibility to any positive findings. So while there are individual studies that appear to show homeopathy having some effect, a comprehensive review of the evidence at all levels fails to support any specific use. And while this failure might not be damning for a new therapeutic approach, after more than 150 years, it is past time that a truly effective therapy should have been able to prove its worth.

The same conclusion has been reached by many others, from the systematic reviews of homeopathic trials and systematic reviews of these systematic reviews, to the formal investigations of governmental agencies such as the British House of Commons Science and Technology Committee and the Australian National Health and Medical research Council. While homeopaths have had more than a century to try, they have not been able to produce a body of scientific evidence to convince anyone but themselves that homeopathy works.

C. Doehring, A. Sundrum. Efficacy of homeopathy in livestock according to peer-reviewed publications from 1981 to 2014. Veterinary Record doi:10.1136/vr.103779

The latest review is the first in veterinary medicine not written by the group of homeopathy advocates that has produced the previous systematic reviews. Not surprisingly, it too concludes that despite some trials appearing to show benefits, the scientific literature does not provide good evidence sufficient to validate or recommend homeopathy. As well as reinforcing this consistent finding, it also provides support for a number of the objections that I and others have raised regarding the apparently positive literature often cited by homeopaths to justify their claims, including:

  1. Frequently there is poor reporting of study details, so it is not possible to accurately assess the risk of bias (this, sadly, is a general problem in the veterinary literature, not just in the domain of alternative medicine).
  2. Studies with better control for bias are less likely to show positive results.
  3. Studies published in dedicated alternative medicine journals are more likely to show positive results than those in the mainstream scientific literature, suggesting publication bias.
  4. Positive studies are not replicated. This is key since no single study can prove any hypothesis, much less one as inherently dubious as those behind homeopathy. Consistent findings by different researchers in different settings is required to have confidence in positive effects of a treatment.

The authors made perhaps the most comprehensive search of the livestock literature yet for homeopathy studies. Their goal was to identify any study of homeopathy used in farm animals in a way that might reduce or replace antibiotics, either in the prevention or treatment of infectious diseases or as a growth promoter. Since this is a common use claimed for homeopathy, this is a relevant subject within the larger literature.

From 1981-2014, they found 48 published studies that fit their search criteria. Only 11 of these were double-blinded randomized controlled trials, the best kind of study to evaluate medical treatments. The trials included had a variety of shortcomings. 39 of the studies were considered to have a significant risk of bias based on how they were conducted. Many also included only very small numbers of patients. Some selected a conventional treatment for comparison that did not meet current guidelines or standards for selecting antibiotic treatment, which would have been a misleading comparison.

Slightly over half of the studies showed a positive effect, whereas the rest did not. A number of factors were associated with the chances of a positive finding. For example, the better the study design and the controls used for bias, the less likely a study was to find a positive effect:

Homeopathic trials performed as a single-blind or non-blind RCT, parallel groups or an observational trial (Fig 4) tended to be more frequently efficacious than a double-blind RCT, indicating that positive outcomes may partly be due to a bias caused by a conscious or unconscious preference for a certain treatment.

Altogether, studies with a high possible risk of bias were more prone to report efficacy of homeopathy than studies with a low risk of bias (OR 1.71, 95 per cent CI 0.48 to 6.11, P=0.41 vs OR 0.58, 95 per cent CI 0.16 to 2.09).

Also, studies published in alternative medicine journals were far more likely to show an effect than those published in mainstream journals:

In journals focusing on alternative treatments, 15 of 18 trials reported that the homeopathic remedy tested was effective (odds ratio [OR] 3.75, 95 per cent confidence interval [CI] 0.63 to 22.04, P=0.14), while in journals with a broader focus on veterinary medicine, 12 out of 18 trials found the homeopathic treatment was ineffective (OR 0.27, 95 per cent CI 0.05 to 1.57).

Finally, not a single positive study has been reproduced, which is an essential criterion for establishing an effective treatment:

When taking the total number of studies into account, not even one study was repeated under comparable conditions. Consequently, the existing conditions, which enable a systematic review to be carried out completely are not given. The current evidence of studies providing evidence in favour of homeopathy lacks reproducibility and therefore cannot claim to have sufficient prognostic validity.

This review reinforces the conclusions of previous reviews. Despite 150 years of effort, no reliable, high-quality evidence has been produced showing homeopathy to be consistently effective for any veterinary use. Added to the inherent inconsistency of homeopathic theories with established scientific principles, and the much more rapid and dramatic validation many other treatments have been able to achieve, it is past time to accept that this practice has no value beyond placebo and is inherently a waste of resources and misleading to animal owners.

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A Critical Analysis of a Study of Essential Oils and Apipuncture—Oh, Forget It, This is Just Ridiculous….

I recently ran across a prime example of lousy science done solely for the purpose of propping up alternative-medicine beliefs or practices. Good science aims to discover what is true, not simply buttress one’s existing beliefs or provide marketing material for them. And good medical research requires that there be a reasonable chance the treatment being tested will solve an important clinical problem in a way that improves the welfare of patients. This study fails on those basic criteria, as well as on more technical but still important methodological grounds.

Shin Jin Cheol; Kim SangHun; Park HyungJin; Seo KyoungWon; Song KunHo. Effect of aromatherapy and apipuncture on Malassezia-related otitis externa in dogs. Journal of Veterinary Clinics, 2012, 29, 6, pp 470-473.

Malessezia is a form of yeast normally found in the ears of dogs. In some individuals, these yeast can be present in excessive numbers, and this is usually associated with inflammation and associated discomfort. The fundamental problem is typically not the yeast itself, but the factors that lead to inflammation and overgrowth of yeast. These are often underlying allergies (to dietary proteins or environmental allergens), the conformation of the individual patient’s ear (dogs with long, hairy ear canals and floppy ears are often at greater risk of otitis or inflammation in the ear), and the past history of the patient (recurrent otitis damages the ear canal in a way the increases the risk of future episodes).

Medication to reduce the number of yeast present is often included in treatment of otitis, but it is important to realize the yeast themselves are almost never the problem. Inflammation, bacterial overgrowth, and predisposing factors must also be addressed, or treatment will only provide partial or temporary relief. Most commonly, dogs with yeast otitis are given topical medications with steroids and medications that reduce bacterial and yeast populations. Ideally, if the problem is severe or recurrent, underlying causes are investigated and addressed.

Oral medications are sometimes used, though there is no compelling evidence for their efficacy in yeast otitis. In fact, I found this paper while I was looking for studies that might show whether or not the oral antifungal drug ketoconazole alone was effective in treating yeast otitis. I suspect it rarely is since it addresses only part of the problem, and likely not the most important part in many dogs. In any case, I did not find any such studies, so whether or not this drug is helpful is an open question.

However, in this study ketoconazole is used as a positive control, so the design begins with an unfounded assumption that this treatment should be effective. The comparison is then a combination of essential oils poured into the ear and, for the most ridiculous part, the injection of bee venom into a purported acupuncture point, Small Intestine 19, located next to the opening of the ear canal. So we have a comparison between an unproven oral drug and a variety of other untested chemicals (calling them “essential oils” doesn’t change their status as untested or as chemicals) combined with an insect toxin injected near the ear. Add in the fact that subjects weren’t randomized, investigators weren’t blinded, and the outcome measures evaluated were subjective, and you have the perfect recipe for crappy science:

  1. Start with an implausible but deeply held belief as your hypothesis
  2. Choose an unproven or lousy conventional treatment to compare with your alternative medicine
  3. Make sure the outcome is a judgment call and that you do little or nothing to control for the effects of chance or bias
  4. Toss in some questionable statistical analysis and voilá, you have BOGUS SCIENCE!

In terms of plausibility, a number of essential oils have been shown to have anti-microbial properties in test tubes. Of course, so does bleach and boiling water, so this by itself does little to support their use in actual patients. Bee venom has, not surprisingly, a lot of interesting chemicals in it. However, there is little good quality research, and it has not yet been shown to be a truly effective for any condition, though there might be some potential for medical use in the future. As for injecting it into acupuncture points, which arguably don’t exist anyway, that’s nonsense.  There are a couple of interesting small studies suggesting acupuncture could have some impact on otitis in dogs generally, but these are preliminary, and overall the evidence is too limited to draw a conclusion.

Not surprisingly, given the lack of control for bias, the study showed no difference between the dogs given oral anti-fungal medication and those given essential oil and “apipuncture” treatment. Both groups appeared to improve significantly by 2 weeks, though not at the 1-week assessment. Given the design of the study, there is no way to determine if this had anything to do with the treatments given, or how either would compare with standard therapy, usually consisting of topical medication containing a steroid, antibiotic, and anti-fungal combination.

The group receiving the antifungal medication did show some slight changes in a couple of liver enzymes. This is not unusual with the oral antifungal, and it is not clear this had any clinical significance. Nevertheless, the authors use this as an argument to prefer their alternative therapy.

So we have a comparison between an unproven and not typically used “conventional” treatment and an implausible and unproven alternative with no effort to control for bias or other sources of error. We find no difference between the groups except a bloodwork change of uncertain significance. And the whole focus of the study is treating an aspect of the problem that isn’t generally the cause. What we have is less an argument for the alternative therapy presented than it is a fine example of the misuse of scientific research in alternative medicine.


Posted in Miscellaneous CAVM | 1 Comment

Petition Petco to Stop Selling Worthless Homeopathic Products!

I have discussed many time the evidence that homeopathy is nothing but a placebo. This has moved beyond the realm of reasonable doubt, and despite the misguided advocacy of homeopaths and some consumers, more and more governments (e.g. UK, Australia) are coming to acknowledge that time and money spent on homeopathic treatment is wasted and delays appropriate and effective medical care.

Just as homeopathy is being challenged in the human healthcare field (e.g. disappearing from national healthcare in the UK), so it is being opposed by veterinarians who believe it offers only false promises to pet owners (c.f. efforts in the US, Australia, Europe, and the UK to discourage veterinary homeopathy). While these efforts are not always completely successful they represent a growing recognition that homeopathy offers no real health benefits and that suggesting it might and offering it as a treatment is unethical.

Recently, the Federal Trade Commission (FTC) ruled that over-the-counter (OTC)homeopathic remedies cannot be sold unless there is a clear disclaimer indicating that any claim for actual effects is unscientific and inconsistent with modern medical knowledge:

[Marketers must] 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.

While it is unclear whether this rule will be enforced by the incoming administration, it indicates yet again that regulators are recognizing a duty to protect the public against false and unscientific medical claims for homeopathic products. Veterinary patients deserve the same protection!

I have started a petition on to ask Petco, one of the largest pet supply retailers, to discontinue the HomeoPet OTC product line and all other homeopathic products.


Petco currently sells these remedies in stores and online, through and its subsidiary Foster and Smith. These products clearly intend to falsely imply they can treat medical conditions in pets. With names like “Digestive Upsets,” “Anxiety Relief,” “Skin and Itch,” “Worm Clear,” “UTI+,” and so on, these products suggest they can treat real medical conditions when the evidence is clear and robust that they cannot. This misleads and deceives consumers and endangers pets whose owners waste time and resources on these products instead of seeking real medical treatment.

So how can you help? Well first, SIGN THE PETITION!

In addition, I am writing the company leadership. Since the CEO is  schedule to step down in February, I have addressed my letter to his successor, currently President and Chief Merchant. I encourage anyone concerned about this issue to write the incoming CEO. My letter is copied below,  and you are welcome to reuse any portion of it for your own contact with the company.

Brad Weston
President and Chief  Merchant
PETCO Animal Supplies Stores, Inc.
9125 Rehco Rd.
San Diego, CA

Dear Mr. Weston:

I am writing to ask that your company discontinue selling the HomeoPet product line and all other over-the-counter homeopathic products, whether sold online through and Fosters and Smith or in your retail stores. These products offer no therapeutic benefit to your customers’ companion animals, and they can harm these pets by encouraging owners to delay seeking appropriate veterinary care.

The scientific evidence is clear and robust that homeopathic products lack any benefit beyond placebo.1-2 This is widely accepted by regulators and other government agencies throughout the world.3-4 Here in the United States, the Federal Trade Commission (FTC) recently concluded that marketing over-the-counter homeopathic products constitutes false advertising unless clear disclaimers are present to inform consumers that any claim of benefit for these products is inconsistent with scientific evidence and consensus.

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…

[Marketers must] 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.5

For Petco to stop selling these ineffective products would be in the best interests of your customers, and the animals they care for, and consistent with your company’s mission to provide products that truly support animal health and well-being. Thank you for your attention.


  1. Ernst E. A systematic review of systematic reviews of homeopathy. British Journal of Clinical Pharmacology. 2002;54:577-582.
  2. Shang A, Huwiler-Muntener K, Nartey L, Juni P, Sterne J A C, Pewsner D et al. Are the clinical effects of homoeopathy placebo effects? Comparative study of placebo-controlled trials of homoeopathy and allopathy. Lancet 2005; 366:726-732.
  3. Great Britain. Parliament. House of Commons. Select Committee on Science and Technology. Evidence check 2: homeopathy : fourth report of session 2009-10 : report together with formal minutes, oral and written evidence.
    London : TSO, 2010. Accessed December, 2016 at
  4. Australian Government. National Health and Medical Research Council. Statement on Homeopathy and NHMRC Information Paper – Evidence on the effectiveness of homeopathy for treating health conditions. 2015. Accessed December, 2016 at
  5. United States Government. Federal Trade Commission. Enforcement Policy Statement on Marketing Claims for OTC Homeopathic Drugs. 2016. Accessed December, 2016 at



Posted in Homeopathy | 12 Comments

Glacier Peak Holistics Pet Wellness Life Scan Stress Test or How Much BS Can Fit on One Web Page?

Allergies are a common and frustrating problem for many pet dogs. While the details are incredibly complicated and not completely understood, allergies are the result of inappropriate inflammation and other immune system responses to triggers in the environment. These triggers can be anything from flea saliva to food ingredients to pollens or dust. Dogs with allergies likely have a genetic predisposition to such excessive immune reactions, and early environmental exposure may play a role. While there are many therapies available that significantly reduce symptoms, improve quality of life, and modulate the abnormal immune response that is the cause of allergies, there is no simple or single cure.

The unpredictability of allergy symptoms, their chronic waxing and waning nature, and the lack of a definitive cure make allergies a popular target for alternative therapies. And just as alternative practitioners ignore much of the science behind vaccines in order to promulgate made-up theories that support their own methods, so many CAVM advocates ignore all that is known about the pathophysiology of allergies and the available diagnostic and treatment interventions and instead make up their own unscientific theories to sell alternative allergy treatments. A reader recently drew my attention to a particularly ridiculous example of this that approaches self-parody: Glacier Peak Holistics Pet Wellness Life Scan Stress Test.

What Is It?
This is actually a relatively difficult question to answer since the company materials about the test are mostly faux-scientific gibberish with a lot of repetition of the meaningless term “energy.” Here’s a sample:

Most allergy-type symptoms are not caused by actual allergies at all…Certain stressors in your pet’s diet are more likely the root source of the allergy symptoms.

Because dogs and cats lack the proper digestive enzymes to digest starchy root vegetables, grains and most fruits, feeding these types of foods can contribute to yeast overgrowth and immune system issues.

Traditional medicine usually prescribes steroids that only mask the allergy symptoms by suppressing the natural function of immune system and can cause damaging, irreversible side effects…Sadly, most pet’s allergy symptoms return stronger than before treatment beginning a vicious cycle that has ZERO lasting benefits.

The Pet Wellness Life Stress Scan, formerly “Healthy Dog and Cat Alternative Sensitivity Assessment”, is the original hair and saliva scan for identifying over 300 stressors in your pet’s diet and environment…The Pet Wellness Life Stress Scan uses biofeedback, which has the ability to read the energetic resonance that emanates from the hair and saliva samples.

Biofeedback energy status analysis measures the body’s bio energetic balance or homeostasis in relation to various food and environmental factors that an animal is exposed to.

The Chinese would call this a balance of yin or yang, with the ultimate goal removing or reducing incompatible energetic disturbances that diminish the body’s Qi or life-force. It is well known in TCM, homeopathy and western holistic medicine, that energetic and spiritual disturbances often precedes physical disturbances…It is a non-invasive energetic analysis seeking to identify and diminish non-harmonic energetic factors.

Using biofeedback analysis, the biofeedback device can identify over 300 food and environmental factors that may disturb an animal’s energy balance.

So, how many woo-woo clichés and warning signs of quackery could you spot? A partial list would include:

  1. Rejection of established scientific knowledge- While allergies aren’t completely understood, the idea that they aren’t really allergies or that they are due to vague “stressors” is nonsense. There is extensive scientific evidence demonstrating the causes and processes of allergic problems in humans and dogs which this company ignores.
  2. Dismissal of science-based medicine as “only symptomatic” and causing more harm than good- While much allergy treatment is symptomatic because a true cure would involve either changing the genetic constitution or past exposure of a dog or eliminating all allergens from the environment, which often is not possible, some treatments do address the closest we can get to the root cause by either eliminating the triggers (limited antigen diets, for example) or desensitizing the immune system to prevent the initial inappropriate reaction to antigens (immunotherapy or “allergy shots”).
  3. Focusing on risks and ignoring benefits from conventional treatment- All treatments that do anything at all have both risks and benefits. Steroids (and the many, many other topical and system allergy medications this website neglects to mention) can have risks, especially when inappropriately used. However, they also can give dogs suffering from allergies relief and a good quality and normal length of life, which they might otherwise not be able to have.
  4. The nonsense about “grains” that has become quite the alternative nutrition fad, and which I’ve addressed many times (e.g. 1, 2).
  5. Vague pseudoscientific language that is actually meaningless as used here: biofeedback, energy, energetic resonance, energetic status analysis, homeostasis, non-harmonic energy factors.
  6. Reference to non-scientific folk beliefs or fundamentally religious concepts that must be taken on faith and cannot be evaluated scientifically- Qi, energy, life-force, spiritual disturbances.
  7. Complete absence of any scientific evidence to support the claims made.
  8. Presence of anecdotes and testimonials in place of reliable evidence

Does It Work?
In terms of the test itself, it is pretty easy to recognize the complete lack of validity to it. The concept of energy employed here is vague and mystical with no relationship to the science of allergy medicine. The terms biofeedback and homeostasis have real meanings, but those are unrelated to their use here, which is just a smokescreen intended to make folk beliefs and completely made-up explanations sound scientific. Hair analysis is an old and long-debunked practice, and I have already addressed the bogus use of saliva testing for allergy diagnosis in my respond to Dr. Jean Dodds’ claims about it.

Of course, as is often the case with quack medicine, the promoters try to have their cake and eat it too. In addition to trying to make the test sound scientific, the site clearly implies that the test identifies the cause of allergy symptoms:

More Than an Allergy Test

Certain stressors in your pet’s diet are more likely the root source of the allergy symptoms…

The Pet Wellness Life Stress Scan…is the original hair and saliva scan for identifying over 300 stressors in your pet’s diet and environment.

We can show you what foods and environmental factors are currently impacting your pet’s well-being

However, the company also wants to sound “alternative” and, perhaps, to dodge around legal restrictions on claiming to test for allergies when there is no scientific support for the test they are selling. This leads to the usual empty disclaimers that contradict the clear overall message of the advertisement:

This is not a traditional medical laboratory allergy test…It is complimentary and is in no way meant nor to be inferred as a substitute for traditional allergy testing methods that use blood samples such as the ELISA and antibody testing.  We highly recommend that you consult with your vet if you wish such traditional testing be done for your pet.

The company also can’t legitimately claim to diagnose or recommend treatments for allergies since this requires a licensed veterinarian. Instead, they use a lot of doublespeak to suggest that they can help you solve your dog’s allergy problems without actually saying they offer diagnosis and treatment of allergies:

We have Pet Wellness Coaches standing by to help you understand your results and show you the road map back to balance…Our Wellness Coach will go over the results with you page by page….

Bottom Line
The Glacier Peak Holistics Pet Wellness Life Stress Scan (formerly “Healthy Dog and Cat Alternative Sensitivity Assessment”) is a completely implausible test based on vague, mystical nonsense and pseudoscientific theories that contradict the legitimate scientific evidence regarding the cause and management of allergies. The general concept that hair and saliva testing can identify the causes of allergies is false. The marketing of this test is misleading and contains many of the hallmarks of quack advertising. Dog owners struggling with allergies would be far better spending their time and money consulting a veterinary dermatologist for a science-based approach to helping their canine companions.

Posted in General | 7 Comments

Victory! The Federal Trade Commission Acknowledges that Homeopathy is a Placebo

Last year, two important regulatory agencies in the U.S. undertook to review their regulation of over-the-counter homeopathic remedies. The evidence is clear that homeopathy is nothing more than a placebo, but it has persisted for historical and cultural reasons. As I discussed in an earlier post, the Food and Drug Administration (FDA), which has legal authority over the selling of such remedies, solicited public comment in 2015 on the possibility of changing its very permissive policies on such remedies. That review is still underway.

The Federal Trade Commission (FTC), also took comment on its regulation of the advertising for homeopathic products. While the FTC, unlike the FDA, cannot set conditions for the sale of these remedies nor prohibit their sale, it can require truthful advertising, which in the case of homeopathy would mean declaring it to be a placebo with no scientific basis. Amazingly, that is exactly what the FTC has done in its final report. Here is the core of the findings:

The FTC Act does not exempt homeopathic products from the general requirement that objective product claims be truthful and substantiated.  Nevertheless, in the decades since the Commission announced in 1972 that objective product claims must be substantiated, the FTC has rarely challenged misleading claims for products that were homeopathic or purportedly homeopathic.

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.

In summary, there is no basis under the FTC Act to treat OTC homeopathic drugs differently than other health products.  Accordingly, unqualified disease claims made for homeopathic drugs must be substantiated by competent and reliable scientific evidence.

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.

What the FTC has done is essential what skeptics asked for. Homeopathic remedies may still be sold and advertised, since the agency has no authority to prevent this, but they must be advertised truthfully. This means that any claim that such remedies have any effects must either be supported by legitimate scientific evidence (which is impossible since no homeopathic remedy has ever been scientifically proven to work), or it must be accompanied by a clear statement that the claim is based on 18th century theories unsupported by science and believed by the vast majority of scientists to be false.

I suspect that enforcement of this policy will be limited if not non-existent, especially given the anti-science and post-fact nature of the incoming presidential administration. However, the ruling at least shows that non-politicians in government do hear and consider the voices of skeptics and scientists related to science-policy issues.

In summarizing the comments the agency received during its review, the FTC noted that, “The vast majority of the comments received were from individual consumers who had personally used homeopathic products.” Of 530 public comments received, 400 were from users of homeopathy and 30 from homeopaths. Only 50 individuals (myself included) wrote to express a skeptical view of homeopathy. However, several organizations, including Sense About Science, the Society for Science-based Medicine, the Center for Inquiry, and the Richard Dawkins Foundation for Reason and Science contributed opinions. Ultimately, the logic and evidence of the skeptics won out over the greater number of comments promoting homeopathy through personal faith and anecdote. Though one lesson from this is that skeptics need to get off their lazy butts and share their views more often, a more optimistic lesson is that sometimes science and reason can carry the day even when, sadly, it is the perspective of the minority




Posted in Homeopathy | 2 Comments

Evidence Update: Neutricks Still up to Same Tricks

In 2011, I reviewed a product called Neutricks that claimed to help dogs with cognitive dysfunction, a condition in old dogs roughly analogous to dementia in elderly humans. At the time, there was little evidence to support the claims made for this product. Last year, I wrote an update evaluating a new study in dogs of the supposed active ingredient in this product. This study had numerous flaws and a high risk of bias, and it did not provide convincing evidence to support the use of Neutricks. I recently noticed a few additional facts about this product that add to the existing information which makes me inclined to recommend people avoid it.

The first is a recent study of the human version of the product, Prevagen, which involves flaws and biases similar to the canine study and which once again fails to provide compelling supportive evidence for this product.

Moran DL, Underwood MY, Gabourie TA, Lerner KC. Effects of a Supplement Containing Apoaequorin on Verbal Learning in Older Adults in the Community. Adv Mind Body Med. 2016 Winter;30(1):4-11.

To begin with, this study was published in the journal Advances in Mind-Body Medicine. Not exactly a reputable scientific heavyweight journal. In fact, it appears to exist primarily to publish lightweight and outright woo research not able to meet the standards of mainstream journals. As for the study itself, it showed little difference between the treatment group and the placebo group until some questionable post-hoc subgroup analyses were done. A detailed critique is already available elsewhere.

In addition, I am not the only one who has noticed that the company makes claims that go well beyond reasonable evidence. In 2012, the FDA issued a warning letter to the company, pointing out that not only was it making claims not acceptable under the minimal rules governing dietary supplements, but that since it was manufacturing the active chemical ingredient synthetically, it didn’t qualify as a supplement anyway and needed to be tested and regulated like any other new drug. What is more, the company apparently ignored numerous reports of side effects and failed to comply with quality standards for supplement manufacturing.

Sadly, the staff and political will to follow such letters with meaningful action are rarely available in today’s political climate, so the company continues to make and sell its product without going through the appropriate scientific or regulatory processes of a new drug approval. However, if the company was misrepresenting their product, ignoring reports of possible harm, and not complying with quality control standards for supplement manufacturing for their human product, there is no reason to believe they do any better with the veterinary version Neutricks.

Finally, in 2015 a class action lawsuit was filed against the manufacturer of Prevagen claiming that consumers were being misled by medical claims for which there was no legitimate supporting evidence. The courts rejected this element of the lawsuit on the technical legal grounds that only government regulators can require proof of advertising claims, not private citizens. The court did not make any ruling on the accuracy of the accusation, only that the plaintiff had no legal standing to make it in court.

However, the court allowed to stand the element of the suit claiming that the product could not work because the purported active ingredients either could not be effective taken orally because they would be destroyed by digestion (a point I made also in my original post) or because they were not present in sufficient quantity. The case is still being argued at this time.

Bottom Line

In the five years since I originally looked into Neutricks, no compelling evidence has emerged showing it is a safe or effective treatment for dogs with cognitive dysfunction. Furthermore, the company has been warned by the FDA for making illegal claims about the human version of the product and apparently not properly handling reports of possible adverse effects. The company is also being sued by individuals who feel they were misled by the advertising claims made for the human product. While none of this amounts to conclusive evidence the product doesn’t work or is harmful, it also does not give any reason for confidence in the product or the company’s claims. Though people continue to offer positive anecdotes in response to these posts, the evidence shows that there are also negative anecdotes out there, and that regulatory authorities have concerns about the conduct of the company in promoting its human version of this product. In my opinion, the safest and most rational choice given the current information available would be to avoid this product until better evidence is provided in dogs with cognitive dysfunction.

Posted in Herbs and Supplements | Leave a comment