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Anabolic Steroids


Gerald F. O’Malley

, DO, Grand Strand Regional Medical Center;

Rika O’Malley

, MD, Albert Einstein Medical Center

Last full review/revision Jun 2020| Content last modified Jun 2020

Anabolic steroids are synthetic (man-made) versions of testosterone that are used to increase muscle size.

  • Anabolic steroids are hormones that promote muscle growth and increase strength and energy.
  • Anabolic steroids can also have many side effects, including psychologic (mood swings, aggressive behavior, irritability) and physical (acne, masculinizing effects in women, breast enlargement in men).
  • These substances can be detected in urine for up to 6 months.
  • Treatment involves stopping use.

(See also Drug Use and Abuse.)

Anabolic steroids include the hormone testosterone and related drugs. Anabolic steroids have many physical effects, including promoting muscle growth and increasing strength and energy. Thus, these drugs are often used illegitimately to gain a competitive edge in sports. Users are often athletes, typically football players, wrestlers, bodybuilders, or weight lifters, and most users are male.

Anabolic steroids are used medically to treat low testosterone levels (hypogonadism) and sometimes to prevent muscles from wasting away in people who are confined to bed or who have severe burns, cancer, or AIDS.

The drugs may be taken by mouth, injected into a muscle, or applied to skin as a gel or in a patch.

Athletes may take steroids for a certain period, stop, then start again several times a year. This process is called cycling. Athletes also often use many steroids at the same time (a practice called stacking), and they take them by different routes (by mouth, injection, or patch). They may also increase the dose through a cycle (called pyramiding). Pyramiding may result in very high doses. Cycling, stacking, and pyramiding are intended to enhance desired effects and minimize harmful effects, but little evidence supports these benefits.

At doses used to treat disorders, anabolic steroids cause few problems. However, athletes may take doses 10 to 50 times these doses.


Anabolic steroids have physical and psychologic effects. The more drug is taken, the greater the effect.

Physical effects

The main physical effect of anabolic steroids is

  • Increased muscle size

Other physical effects include

  • Gynecomastia (breast enlargement) and shrunken testicles with decreased sperm count in men
  • Virilization (masculinizing effects) in women, such as baldness, excess body hair (hirsutism), an enlarged clitoris, a deepened voice, shrunken breasts, and thinning of the lining (atrophy) of the vagina.

Gynecomastia in men and masculinizing effects in women may be irreversible.

Increased acne is common in both sexes. Libido may increase or, less commonly, decrease. Aggressiveness and appetite may increase. In younger adolescents, steroids can interfere with the development of arm and leg bones.

Long-term use can cause the body to produce too many red blood cells and abnormal levels of fats (lipids) in the blood. Low-density lipoprotein (LDL)—the bad—cholesterol levels increase, and high-density lipoprotein (HDL)—the good—cholesterol levels decrease. Severe cardiovascular complications, including high blood pressure, stroke, heart attack, and blood clots, are reported with the use of anabolic steroids.

Psychologic effects

Steroids have several psychologic effects (usually only with high doses):

  • Wide and erratic mood swings
  • Irrational behavior
  • Increased aggressiveness (steroid, or "roid," rage)
  • Irritability
  • Increased sex drive (libido) in men and sometimes in women
  • Depression


  • Urine tests

Urine tests are done to check for breakdown products of anabolic steroids. These products can be detected up to 6 months after use is stopped.


Adolescents and young adults should be taught about the risks of taking steroids starting in middle school. Also, programs that teach alternative, healthy ways to increase muscle size and improve performance may be useful. Such programs emphasize good nutrition and weight training techniques.


  • Stopping use of steroids

The main treatment is stopping use. Although physical dependence does not occur, psychologic dependence, particularly in competitive bodybuilders, may exist. Gynecomastia (enlarged breast tissue in men) may require surgical reduction.

More Information about Anabolic Steroids

  • National Institute on Drug Abuse (NIDA): Anabolic steroids
  • Substance Abuse and Mental Health Services Administration (SAMHSA)

Drugs Mentioned In This Article

Generic Name Select Brand Names
testosterone DELATESTRYL

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