Tuesday, February 24, 2009

Is Your Horse's Pergolide Stable?

Long before it became a preferred treatment for equine Cushings, pergolide was used to treat Parkinson's Disease in humans. Serious side effects, however, led the FDA to remove pergolide from the market for human use in 2007. Since then, only certain forms of pergolide have been available for use in horses, but they had not been evaluated for stability, among other things.

Stability and Efficacy of Compounded Pergolide Examined outlines a few recommendations, based on findings of a study conducted at the College of Veterinary Medicine at North Carolina State University:
>Store compounded pergolide mesylate products in a dark container, protected from
light;
>Refrigerate products to help minimize excessive degeneration;
>Dispose of products within 30 days from date of compounding;
>Evaluate the color of the product prior to each use and discard any pergolide product that has undergone any change in color, and;
>Request that your pergolide is compounded by pharmacists that use only the officially recognized formula (by the United States Pharmacopeial Convention).

Based on comments by a regular TREES visitor, these suggestions do seem to have a big impact on how well pergolide works. Here, we only purchase two weeks worth of pergolide at a time from a pharmacy that does not compound the drug until it is ordered and it is always kept refrigerated. Our visitor has mentioned that other farms using different forms of pergolide or different storage techniques seem to see more obvious symptoms than we see here. That is far from scientific proof, of course, particularly since each Cushings patient may exhibit different symptoms to varying degrees and may respond to treatment differently than other horses. We know we are paying more for our pergolide than some other people, but it may be worth the extra expense if quality treatment helps to prevent serious complications such as laminitis.

When visiting the link to the article, please also pay attention to the sidebar concerning "Human Health," particulary if you are using pergolide powder:
In response to the demonstrated stability concerns of liquid pergolide products, there has been some discussion regarding the use of bulk pergolide powder in equine practice. According to pharmacists, this is not a realistic alternative to the, "pergolide problem" as inhalation or ingestion of pergolide mesylate by humans is unsafe. In particular, inhaled or ingested pergolide can cause damage to the central nervous system and cardiovascular system (heart and lungs).

No comments: