Dihydrotestosterone Remains Within Normal Range in Men Under Long Lasting Testosterone Therapy (TTh)

The major goal of androgen therapy is to achieve testosterone levels as close to physiological concentrations as possible.For some androgen-dependent functions, testosterone is a pro-hormone, peripherally converted to 5a-dihydrotes-tosterone (DHT) and 17b-oestradiol of which the levels preferably should also be within their normal physiological ranges.In this study, the resulting plasma DHT levels in 122 hypogonadal men treated with a novel testosterone treatment modality: parenteral long-acting testosterone undecanoate (Nebido), were investigated.Following the treatment, there were no abnormally high/ low plasma DHT levels; levels varied between 86 and 511 ng l)1 (normal range:40-575 ng l).In conclusion, treatment with testosterone undecanoate generates physiological levels of DHT.Prostate safety parameters did not undergo changes.