Overview

What is gynecomastia?

Gynecomastia is a common condition which results in enlarged male breast tissue. It can be seen in males of all ages, but usually occurs during the newborn period, puberty and older adulthood. There are many causes for gynecomastia, most commonly an imbalance of the hormones testosterone and estrogen.

How does gynecomastia affect my body?

Gynecomastia can be seen as a button-sized growth underneath the nipple. You may be able to see this as a breast lump or feel it when you press on the area. The lump may move easily within the breast tissue and may be tender to touch. Breast lumps and breast enlargement may occur in one or both breasts.

How common is gynecomastia?

Gynecomastia is the most common male breast disorder. It affects between 50 to 65% of boys and men worldwide.

Who might have gynecomastia?

Gynecomastia can occur at different times, including:

• Birth: More than half of male newborns have enlarged breasts, or breast buds. This condition is due to the mother’s estrogen levels. The enlarged breasts usually go away within a few weeks.
• Puberty: More than half of teenage boys have some degree of breast enlargement. Fluctuating hormones, including drops in testosterone and surges in estrogen, cause breast tissue to grow. The condition goes away as hormone levels even out — a process that takes about six months to two years to complete.
• Adulthood: Enlarged breasts are more common in men over 50. With age, men’s bodies produce less testosterone. They may also have more body fat, which stimulates estrogen production and breast tissue growth.

Possible Causes

What causes gynecomastia?

An imbalance between estrogen and androgen hormones typically causes gynecomastia. Men’s bodies usually produce small amounts of estrogen, the hormone that controls breast growth. If your body produces too much estrogen, or you have low testosterone (hypogonadism), your breasts may enlarge.

Sometimes people with obesity develop enlarged breasts due to excess fatty tissue. This condition is known as pseudogynecomastia.

What conditions cause gynecomastia?

Certain conditions can cause male breast enlargement, including:

• Adrenal tumors.
• Alcoholism.
• Kidney disease or kidney failure.
• Klinefelter syndrome (an inherited condition).
• Liver disease.
• Thyroid disease.

What medications or drugs cause gynecomastia?

Gynecomastia can result from taking medications to treat:

• Anxiety and depression.
• Bacterial and fungal infections.
• Enlarged prostate.
• Heartburn and peptic (stomach) ulcers.
• Heart failure and high blood pressure.
• Male infertility (by taking human chorionic gonadotropin, or HCG).
• Substance abuse (by taking methadone).

These drugs also can cause breast swelling:

• Amphetamines, marijuana and opioids.
• Anabolic steroids used to build muscle.
• Lavender oils and tea tree oils (found in herbal supplements and skin care products).

Care and Treatment

How is gynecomastia diagnosed?

Your healthcare provider will assess symptoms, perform a physical exam and review your medical and family history. A blood test may also be recommended to check hormone levels.

Because both gynecomastia and breast cancer cause breast lumps, your provider may order a:

• Breast ultrasound to view detailed images of breast growths.
• Mammogram to examine unusual growths or changes in breast tissue.

How is gynecomastia managed or treated?

Some people don’t want or need treatment for gynecomastia. If a medication or other substance is causing breasts to enlarge, you may need to stop using the drug or switch to a different one. If a disease is the cause, swelling should go away with disease treatment.

Some men choose to get breast reduction surgery. During this procedure, a plastic surgeon removes breast tissue to make breasts smaller.

Can gynecomastia be prevented?

You can’t prevent many of the hormone changes that cause gynecomastia. If needed, you may reduce your risk of breast enlargement by switching medications or seeking treatment for a substance use disorder.

When to Call the Doctor

When should I call my healthcare provider about gynecomastia?

You should call your healthcare provider if you experience:

• Breast lump, breast pain or unusual breast changes.
• Itchy breast or underarm area.
• Nipple discharge.

What questions should I ask my doctor?

You may want to ask your healthcare provider:

• Why did I get gynecomastia?
• Should I switch medications to stop breast enlargement?
• What is the best treatment for gynecomastia?
• How long will my breasts be enlarged?
• How can I prevent getting enlarged breasts again?
• Should I get screened for breast cancer?
• Should I watch for signs of complications?