It is generally accepted that chemical testing of biologic fluids is the most objective means of diagnosis of drug use. In recent years saliva has attracted much attention. The prime advantage of saliva is that it offers non-invasive, stress-free and real-time repeated sampling whereas blood collection is undesirable, difficult and expensive. In addition, it is known that androgens such as testosterone can be assayed in saliva, as these steroids pass the endothelial-epithelial barriers by passive diffusion. Nevertheless, the correlations of blood, urine and saliva concentrations are not well documented. In recent reviews, it is pointed out that salivary hormone analysis could be a promising method for sports medicine and doping control, but much work is needed before the use of saliva samples in this area receives the acceptance. According to recent studies the increase of testosterone concentration in saliva is significantly higher than alterations of steroid concentrations (or ratios) in blood or urine. Saliva concentration may therefore serve as screening parameter to select suspicious cases for further target evaluation (e.g. by IRMS). This may be beneficial to identify cases of transdermal administration of low steroid doses. It is therefore the aim of the present project to detect administered testosterone in saliva and compare these levels to those in blood and urine. The intention is not to detect high dosage but low dosage abuse of testosterone, as a single-dose by patch application. From the practical point of view saliva could offer a complementary specimen for a pre-screening of testosterone. So it could be assumed that salivary testosterone exceed upon plasma and/or urine levels. So the present study could be the base for a new method to preselect the suspicious samples for testosterone abuse.