[Testosterone replacement: application and surveillance].

Male hypogonadism is based on an insufficient gonadal function, especially testosterone deficiency. The decreased endogenous production of testosterone can be acquired or congenital. The lack of testosterone results in typical clinical symptoms which give initial indications for testosterone replacement therapy. Nevertheless, less than 10% of the affected patients receive an adequate treatment. Presently different preparations and application forms are available for the therapy of hypogonadism with testosterone. Intramuscular, peroral, transdermal, sublingual and subcutaneous preparations show differences in pharmacodynamics, pharmacokinetics, price and handling. Therefore these formulations should be applied individually. Regular clinical and chemical controls of effect, side effects and contraindications are essential along with long-term substitution.