A case of positive doping associated with a botanical food supplement.

In this manuscript the chemical and pharmacokinetic evaluation of a doping case associated with the use of an Ephedra-labelled dietary supplement is reported. The urine of a Dutch professional cyclist was found to be positive for norpseudoephedrine at a doping control. An inquiry revealed that the cyclist had consumed a liquid herbal food supplement with Ephedra as one of its 15 declared ingredients. Chemical analysis revealed concentrations of 6.8-8.2 mg/ml of norpseudoephedrine and 0.02-0.03 mg/ml of ephedrine in several batches, which could have caused the positive doping test. Since the International Olympic Committee (IOC) list of doping substances comprises several substances which occur naturally in botanicals, doping agents like ephedrines and/or caffeine may be taken unwittingly in the form of herbal food supplements. In this case, the predominance of norpseudoephedrine over ephedrine was explained by spiking with norpseudoephedrine, showing that adulteration of herbal food supplements with undeclared agents also have to be taken into account. Our report demonstrates a need for improved quality control of herbal food supplements.