Androgens | Research & Encyclopedia Articles

Androgens

Androgens are a group of chemically-related male sex hormones. They can be produced naturally by the body or be manufactured synthetically and then administered to the individual. Androgens belong to a group of hormones called steriod hormones. Testosterone is the most abundant androgen in the male body.

Testosterone is responsible for the development of male sexual characteristics. In normal males, it is produced at the onset of puberty by the testes in response to stimulation by hormones called gonadotrophins that originate in the anterior pituitary gland and the hypothalamus, a part of the brain.

Testosterone causes boys to acquire the sexual characteristics of men. In response to testosterone, the penis, testes, and scrotum grow and the voice deepens. Hair grows on the body and face and the skin becomes coarser. Androgens also stimulate growth. Not only do boys grow taller during puberty, they also develop larger, bulkier muscles in the arms, shoulders and thighs that give them their distinctly masculine shape. Androgens allow ejaculations to begin, usually between the ages of 11-15, in response to sexual fantasies or masturbation. After puberty, the testes produce testosterone for the rest of a man's life, but in decreasing amounts as men reach their late 40s or early 50s.

Testosterone is not the only androgen in the body, but it is by far the most important one. The adrenal cortex, or outer part of the adrenal gland, a small gland located above the kidney, also produces androgens as well as hormones that help regulate water balance in the body. These adrenal androgens cause the same effects as testosterone, but are produced in much smaller quantities.

Women produce androgens in the ovaries and adrenal cortex. Almost all of a woman's androgens are immediately converted by the body into estrogens, the hormones that give women their female sexual characteristics. The small amount of androgens that remain unconverted play a role in determining the sex drive of women and in slowing bone loss or osteoporosis. In Cushing's disease, the adrenal cortex overproduces hormones. This excess of androgens may cause some women with Cushing's disease to develop male characteristics such as facial hair or a deep voice.

Androgens have legitimate therapeutic medical uses. They are prescribed for men when testosterone is not naturally produced by the body. Synthetic androgens come in the forms of a pill, a patch, and injectable forms. They are prescribed more commonly for male children to make undescended testes descend, or to bring about male puberty when it is seriously delayed. In adult men, androgens are used to correct natural hormone deficiencies and to reduce "male menopause" symptoms such as lack of sex drive, anxiety, and depression. Some androgens are used to treat dwarfism because of their ability to stimulate growth.

Legitimate medical uses of androgens in women include their use in treating some kinds of breast cancer and anemia. Sometimes androgens are given after childbirth to reduce breast pain and fullness in women who choose not to breast feed. Women who undergo gender change are also given androgens to increase their male characteristics.

Androgens are part of a group of drugs known as anabolic steriods that are used illegally by some athletes in an attempt to increase their muscle bulk and strength. These black market androgens are usually taken in doses many times higher than would be prescribed for medical reasons. Their use has been outlawed by the International Olympic Committee and most other national and international organizations regulating sports competitions.

Serious, sometimes life-threatening side effects may occur when androgens are taken. They may cause liver disease, stimulate prostate cancer, interfere with sperm production if taken in high doses, cause acne, irregular menstrual cycles in women, dizziness, headache, nausea, weight gain, jaundice, and swelling of the feet in both men and women. Androgens interact with many common medications and should never be taken without medical supervision.