The male hormone responsible for maintaining male sex characteristics, testosterone is also found in women in small quantities. Low testosterone affects sexual functioning and also increases the risk of developing osteoporosis. Decreased muscle mass, anemia, increased risk of cardiovascular disease and depression may also accompany low testosterone levels. Testosterone replacement therapy for men is available, but it comes with its own set of risks. Testosterone replacement therapy for women is still considered experimental.
Male Sex Organ Effects
Testosterone replacement therapy stimulates prostate growth. The prostate enlarges in 12% of men taking testosterone, a condition called benign prostatic hypertrophy, or BPH. Urinary symptoms of BPH include urinary frequency (especially at night), urgency to urinate, incontinence, involuntary leakage and a weak urinary stream. Testosterone replacement therapy may increase the risk of prostate cancer, according to the Merck Manual website. Sperm counts may decrease, and testicles may shrink or become sensitive to touch. Male breast tissue may increase and be tender to touch as well.
Skin Reactions
Itching and irritation occurs at the site of application with transdermal patches 37% of the time, patches saturated with medication and placed on the skin to be slowly absorbed, according to Drugs.com. Burning, blistering and redness are also common side effects. Acne occurs in 8% of men taking the drug, and hair loss affects 1%.
Other Side Effects
Fluid retention from testosterone replacement therapy may cause ankle and leg swelling, worsen hypertension and contribute to congestive heart failure, says Michael Werner, M.D., a urologist and specialist in male infertility and male sexual dysfunction. Oral forms of testosterone can cause liver damage as well. Headache, high blood pressure and an increase in sleep apnea (periods where a person stops breathing while asleep) may occur when taking testosterone replacement therapy. Red blood cell production may increase. This condition, known as polycythemia, may increase the risk of heart attack, stroke and clot development, Werner reports. Nervousness, anxiety and depression may also occur.
Female Side Effects
Women taking testosterone may develop acne, male pattern baldness or hair loss, or hirsuitism (hairiness). Breasts may decrease in size, while the clitoris size may increase. The voice may deepen as well --- an effect that may be permanent, even after discontinuing the drug, the University of Michigan Medical Center website explains. Menstrual cycles may become irregular in women still menstruating. Anger and hostility issues may escalate.
