dextromethorphan

As a Clinical Pharmacologist (human) and an avid horse player, I have grown tired of these instances of biologic samples from horses having banned substances found and the "interesting" explanations as to how the exposure happened. One recent example was a story of a horse in which three samples of blood had metformin (a drug used to treat type II diabetes in humans) detected. The explanation was that a groom and later the trainer was taking metformin and "touched the horse's face." This explanation is questionable from a clinical pharmacology...