A Lechuza pony stands ready for play.
Image: New York Social Diary (2008).
The mysterious deaths of twenty-one Venezuelan polo horses was apparently due to a mistake by the pharmacy that incorrectly prepared the vitamin-and-electrolyte cocktail that was injected into these horses prior to their match on Sunday. A chemist at Franck’s Pharmacy in Ocala, Florida added ten times the requested dosage of selenium to the cocktail. It appears this was an error and not the result of foul play.
The cocktail injected into the Lechuza Caracas horses was based on a commercial supplement called Biodyl. It is a vitamin and mineral supplement made in France, and is widely used there and in other countries, but it has never been approved for use in the US.
Biodyl is advertized as “the power booster” because it supposedly aids recovery from fatigue.
“When you talk about polo ponies, we consider them equine athletes,” said Don Dufresne, who describes himself as an equine legal expert and horse lover. “A horse is so important to your game as a player, you want the horses to be as healthy as they can be, to last as long as they can. You don’t want to overexert a horse. A tired horse is an unsafe horse.”
Apparently, injected vitamin and mineral supplements are commonly used in the performance horse industry in the United States to prevent muscle cramps and help them recover after the events.
“Supplements are used to maintain the levels of electrolytes in the body,” said Loyd V. Allen, Jr., editor of the International Journal, Pharmaceutical Compounding. “There is a lot of energy expended during those matches and that puts additional stress [on the horses]. It’s just to help to keep things where they should be.”
But mimicking the formulation of an unapproved supplement appears to violate federal law, according to FDA officials, because compounding pharmacies are only allowed to reproduce drugs that are unavailable in the United States in an emergency.
“The pirated drugs can present a risk to horses because they don’t go through the FDA approval process,” said Dr. Eleanor Green, dean of Texas A&M University’s veterinary college and past president of American Association of Equine Practitioners. “So there’s no way to know for sure that it contains the right drug or the right amount of the drug.”
Biodyl is given to high performance horses several days prior to a race or other strenuous event. According to a Biodyl website, this supplement contains vitamin B12 (cyanacobalamin), adenosine triphosphoric acid (ATP), potassium (potassium aspartate hemihydrate), magnesium (magnesium aspartate tetrahydrate) and selenium (sodium selenite). It is administered either in drinking water or by injection into either the muscles (IM) or a vein (IV).
Anonymous sources told La Nación, the national Argentinian newspaper, that the veterinarian’s prescription requested 0.5 mg of sodium selenite per milliliter of the cocktail, but the chemist added 5 mg, or ten times that amount. According to the National Research Council, a single minimal lethal oral dose of sodium selenite in horses is 3.3 mg/kg, but a fatal injected preparation, such as what these horses received, contains a much smaller concentration.
“Horses need selenium. It’s in their diet, said Dr. Green. “But in general selenium in high doses can be toxic.”
Selenium is a naturally-occurring mineral that is essential to good health in tiny amounts, but it is fatal in large doses. Symptoms of selenium poisoning include pulmonary edema, reduced blood pressure, unconsciousness and death — which are consistent with the symptoms observed in the stricken polo horses.
Franck’s Pharmacy, which also compounds drugs for people, will probably be sued.
“Everybody wants to ensure that what their horses are getting is correct and is not going to harm their horse. I thing everybody is going to become more aware of this and more cautious.”
The FDA has not yet commented on the pharmacy’s revelation.