Banamine Contamination

A study conducted by researchers at the Swedish University of Agricul-tural Science reported that flunixin (Banamine) given IV or orally (granulate in oats) could contaminate stalls and cause future, untreated horses to test positive for the medication because of environmental contamination. This means that a horse which was not treated with flunixin and which occupies a stall immediately after a treated horse can have a positive drug test for Banamine.

Marianne Sloet, DVM, PhD, Dipl. ACVIM, head of the Equine Internal Medicine Clinic at Utrecht University in The Netherlands and a member of The Horse Editorial Advisory Board, said she knew one of the researchers, and that the university itself was known for solid research projects. Sloet also serves as an FEI veterinary delegate at various competitions in Europe. She said that it is common at competitions in Europe for a groom to clean a stall, place the horse from the next stall into the clean one, then clean that horse's stall. The domino effect is that each horse is moved into a new stall each day. She said based on the Swedish research, it seems possible for a horse to "pick up" enough flunixin in the environment to test positive. Therefore, her advice was "don't change boxes" when a horse has been treated. (Several medications are known to be able to contaminate a horse's environment for extended periods, including isoxuprine.)

In the flunixin study, two geldings were given flunixin (1.1 mg/kg) daily for five days. The drug was administered IV in one study, and orally (granulate in oats) in two other studies. In the study where IV flunixin was used and the study where oral Banamine was used, the medicated horses were removed from their boxes after cessation of treatment and replaced with unmedicated horses. Urine was sampled from all horses 14-21 days after each study.

The two unmedicated horses from the IV study had up to 16 and 21 ng/mL flunixin in their urine, respectively, when tested. The last traces of flunixin were found on Days 3 and 4.

The two unmedicated horses from the oral Banamine study had a maximum of 65 and 78.2 ng/mL flunixin in their urine, respectively. On the last day of urine sampling (14 days after placement in the stall where medicated horses were removed), one of the horses still tested at 8 ng/mL.

In a third study, an unmedicated horse was placed in a box stall between two medicated horses. The untreated horse stabled between the medicated horses did not excrete flunixin in urine in detectable amounts.

The researchers summed their study up by writing: "The result from this study indicates that there is a large risk of contamination after oral as well as IV administration of flunixin. Therefore, we recommend an isolation box for medication of competition horses."

About the Author

Kimberly S. Brown

Kimberly S. Brown was the Publisher/Editor of The Horse: Your Guide To Equine Health Care from June 2008 to March 2010, and she served in various positions at Blood-Horse Publications since 1980.

Stay on top of the most recent Horse Health news with FREE weekly newsletters from Learn More