Testosterone replacement therapy for male hypogonadism (body doesn't produce enough testosterone) when testosterone deficiency has been confirmed by clinical features and biochemical tests.
How it works
The effects of testosterone in humans and other vertebrates occur by way of two main mechanisms: by activation of the androgen receptor (directly or as DHT), and by conversion to estradiol and activation of certain estrogen receptors. Free testosterone (T) is transported into the cytoplasm of target tissue cells, where it can bind to the androgen receptor, or can be reduced to 5?-dihydrotestosterone (DHT) by the cytoplasmic enzyme 5?-reductase. DHT binds to the same androgen receptor even more strongly than T, so that its androgenic potency is about 2.5 times that of T. The T-receptor or DHT-receptor complex undergoes a structural change that allows it to move into the cell nucleus and bind directly to specific nucleotide sequences of the chromosomal DNA. The areas of binding are called hormone response elements (HREs), and influence transcriptional activity of certain genes, producing the androgen effects.
Common side effects
Frequent and excessive erections of penis, Prostate cancer, Depression, Gastrointestinal bleeding, Glucose intolerance, Development of breasts in men, Headache, Increased calcium level in blood, Increase haematocrit, Increased bone growth, Increase in skeletal weight, Increased ldl cholesterol level in blood, Increased vascularity of the skin, Spermatogenesis suppression (azoospermia)