The results of the “Clenbuterol plasma concentrations after therapeutic administration in fit Standardbred horses: threshold recommendations” study published online after peer review in
Comparative Exercise Physiology clearly demonstrate and recommend the need for different withdrawal times and threshold levels for harness racing than the current standards that exist for Thoroughbred and Quarter Horse racing.
The goal of this study was to identify a withdrawal time guideline for use of clenbuterol at dose levels approved by the United States Food and Drug Administration (FDA) in harness racing, where horses may start (race) at seven-day intervals.
Three members of the Harness Racing Medication Collaborative — Kenneth McKeever, PhD FACSM; George Maylin, DVM, MS, PhD; and Clara Fenger DVM, PhD, DACVIM — collaborated on the study.