Dietary supplements containing prohibited substances.

Dietary supplement use among athletes to enhance performance is proliferating as more individuals strive for obtaining that chemical competitive edge. As a result the concomitant use of dietary supplements containing performance-enhancing substances of those falling in the categories outlined in the current review, can also be expected to rise. This despite ever-increasing sophisticated analytical methodology techniques being used to assay dietary supplement and urine samples in doping laboratories. The reasons for this include that a variety of these chemical entities, many of them on the prohibited drug list of the WADA, are being produced on commercial scales in factories around the world (ephedrine and pseudoephedrine, sibutramine, methylhexaneamine, prohormones, 'classic' anabolic steroids, clenbuterol, peptide hormones etc.), aggressive marketing strategies are being employed by companies and these supplements can be easily ordered via e.g. the internet. It can also be anticipated that there will be an increase in the number of supplements containing 'designer' steroids and other 'newer' molecules. Chromatographic techniques combined with mass spectrometry leading to identification of molecular fragments and productions will assist in determining these substances. To prevent accidental doping, information regarding dietary supplements must be provided to athletes, coaches and sports doctors at all levels of competition. The risks of accidental doping via dietary supplement ingestion can be minimized by using 'safe' products listed on databases, e.g. such as those available in The Netherlands and Germany.