The high-profile deaths of 21 polo ponies at the U.S. Open Polo Championship, caused by an overdose of selenium, has brought the issue of compounding back into prominence.
The horses collapsed at the International Polo Club Palm Beach in Wellington, Fla., on April 19, most dying hours later. Franck's Pharmacy, Ocala, Fla., acknowledged four days later it made an error when mixing a medication for the ponies. Jennifer Beckett, chief operations officer of Franck's, said in a statement that "an internal investigation revealed the strength of an ingredient in a medication mixed at the request of a veterinarian was incorrect." The compounding pharmacy has no history of complaints or discipline listed on the state Department of Health's Web site.
Twenty-one polo ponies (not pictured here) died shortly after being injected with a compounded
drug before the U.S. Open Polo Championship.
Although Beckett did not name the ingredient or the medicine, a statement released that same day by the Venezuelan polo team, Lechuza Caracas, indicated that a Florida-licensed veterinarian had ordered a vitamin mixture similar to Biodyl, a supplement that is not approved by the Food and Drug Administration.
The FDA has said it cannot comment specifically on the case because it is still investigating the matter.
Biodyl is a mixture of vitamin B-12 and selenium and other minerals. Used in Latin America, Europe, and Asia, it is manufactured by Merial. The drug is used to treat muscle fatigue and exhaustion in horses and other animals, and the company has documented only one adverse reaction in more than two million doses.
The University of Florida College of Veterinary Medicine's Florida Racing Laboratory determined the next week that the animals had 10 to 15 times the normal amount of selenium in their blood, and 10 to 20 times the normal amount in their liver, said Florida's state veterinarian, Dr. Thomas J. Holt.
This isn't the first time a compounding mishap has become a public incident. In 2005, a group of racehorse owners sued a New Jersey compounding pharmacy, claiming it had incorrectly mixed a product that led to the deaths of three horses and the serious injury of another. The case was settled in 2007 after testing concluded that the medicine's potency was mixed at the concentration that had been advertised (see JAVMA, Dec. 1, 2005).
Following this most recent incident, Dr. Eleanor M. Green, immediate past president of the AAEP, reaffirmed the association's position on drug compounding, including the importance of drug compounding for equine patients, because FDA-approved drugs are not available for all important health needs. The AAEP and the AVMA support the responsible, safe use of compounded drugs and encourage veterinarians to become knowledgeable about the subject to make appropriate recommendations for the patient being treated.
Veterinarians should be aware that without FDA approval, there is no way to ensure a product contains the right drug in the right amount and is packaged correctly, Dr. Green added. She pointed to several studies in which unbiased rearchers analyzed compounded products, with results ranging from no active ingredient to higher concentrations than on the label. She referred to other studies that have found higher percentages of those errors in compounded products as compared with FDA-approved drugs.
Dr. Green went on to say that while the issues surrounding compounded drugs remain gray, the AAEP recognizes their importance when an FDA-approved product is not available for an important health need.
Dr. Elizabeth Curry-Galvin, director of the AVMA Scientific Activities Division, acknowledges that compounding does have its inherent risks, such as lacking the production safeguards FDA-approved drugs have.
The FDA doesn't track or compile statistics on the prevalence of compounded drugs; however, Dr. Bernadette M. Dunham, director of the FDA Center for Veterinary Medicine, said, "We're concerned about veterinarians and pharmacies that are manufacturing and distributing unapproved animal drugs in a manner clearly outside the bounds of traditional pharmacy practice."
For more information on drug compounding, including AVMA policies, click here. The American Association of Equine Practitioners also has resources available, including the AAEP position statement "Equine Veterinary Compounding Guidelines," an overview of legal issues, and introductions to the basic principles of compounding. They can be found on the AAEP Web site, www.aaep.com, by clicking on the "Learn More About Drug Compounding" link.