In men, they include a short-term increase in the sex drive, followed by a suppression of natural testosterone output and potential shrinkage of the testes. Another common side-effect is gynecomastia (deposits of estrogen in the area of the nipple.
For women, a very dangerous side-effect is masculinization due to the androgenic effects of the drugs. This can include deepening of the voice, menstrual irregularities, development of facial hair, clitoral enlargement and even the appearance of male-pattern baldness.
Increased acne is a problem for both genders. Depending on the particular drug used, anabolic steroids can also increase aggression and irritability, cause changes in blood-pressure and blood chemistry (HDL levels, for example) and acne.
Using anabolic steroids is particularly dangerous for teenagers. In addition to interfering with the normal effect of hormones on a growing body, there can also be a premature of the epiphysis, the end of the bone, resulting in stunted growth.
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