To report the experience with treatment of hypogonadal men with the scrotal application of testosterone patches.Prospective and descriptive.In 12 unselected hypogonadal men (aged 27-58 years; serum concentration of testosterone < 10 nmol/l) who complained of adverse effects of oral androgen treatment, the treatment was changed to scrotal application of testosterone patches (Testoderm). First the androgen substitution was stopped for 6 weeks. Follow-up was 4-5 years, during which regular laboratory tests were carried out, the patients filling in questionnaires regarding their general mood and the frequency of sexual feelings/activities.Testosterone levels reached physiological values and a beneficial effect was observed on general mood and sexual functioning. These effects remained stable throughout the entire period of 4-5 years of study. Skin reactions occurred in 2 men. Dihydrotestosterone levels increased to supraphysiological values. Other clinical, biochemical and haematological parameters did not reveal any detrimental effects. The patch, which should be applied to a dry and shaved scrotal skin, was a satisfying androgen replacement therapy for more than 4 years in 7 out of 12 men.In this open study in hypogonadal men with complaints about previous testosterone therapy, scrotal testosterone patches were a useful therapy, leading to the testosterone levels in the physiological range.