I was recently asked by a reader to comment on yet another product marketed for arthritis treatment in dogs and cats: Duralactin. Because arthritis is a very common disease for which there is no definitive cure, it is a popular target for commercial remedies. I have reviewed many of these, but of course there are far more out there I have not addressed. Some, like non-steroidal anti-inflammatory drugs (NSAIDs) are well-researched and their risks and benefits are clearly known. Others, like glucosamine, are quite popular despite little or no evidence of efficacy. Some, like homeopathy, are certainly useless quackery. Duralactin falls into that enormous area of remedies that have so little evidence associated with them almost nothing definitive can be said about their safety or efficacy.
What Is It?
According to the manufacturer, Duralactin is “a patented milk protein concentrate from the milk of hyperimmunized cows.” That sounds very “science-y,” but it really isn’t very revealing. Theoretically, this means the product contains antibodies extracted from the milk of cows stimulated by some means to produce those antibodies. What these antibodies are, how they were produced and processed, and of course what if anything they do for patients with arthritis is not revealed.
Does It Work?
I have not been able to find any published research evidence to answer this question. This is never a good sign. In fact, marketing a product with vague ingredients described in “science-y” language and supported primarily by anecdotes and testimonials is part of a constellation of warning signs for snake oil.
The company does refer to some in vitro experiments which suggest that injecting cows with a bacterial vaccine can stimulate production of compounds in the milk that reduce the activity of some cells involved in the inflammatory response. It is a long, long road, however, from there to a clinical therapy for arthritis, and the company does not appear to have paved the way with much relevant research.
The company also refers to a clinical trial comparing the product to a placebo in dogs. The value of this evidence is, however, quite low as it is a study performed by the company and not apparently published in the scientific literature. Even the limited report available on the company web site suggests some problems with the study. Fifty dogs entered the trial but only 35 completed it, which is a pretty high dropout rate which could easily bias the results. Outcome measures were entirely subjective, and the reported response ranged from 10-14 points over placebo on a 100 point scale, which is of questionable clinical significance.
The company does, of course, offer plenty of testimonials to suggest the product works well, but it is well established that such testimonials are highly biased and misleading.
Is It Safe?
Once again, the answer has to be “Who knows?” The company reports no adverse effects in their unpublished clinical study, but without formal assessment under more reliable conditions, the risks are, like the possible benefits, unknown.
Ultimately, real proof that a medicine is safe and effective requires careful, rigorous, and often expensive and time-consuming research. It is easier and cheaper for companies to produce supplements that can be marketed without this level of proof and then provide far less reliable sources of evidence that their products do more good than harm. Duralactin may well have benefits for patients with arthritis, though there is currently little to support this claim. And while there is no obvious reason to think it is harmful, without real research this is as much of a guess as the question of whether or not it helps.