Gynecomastia (guy-nuh-ko-MAS-tee-uh) happens when a male develops breasts. In young males, the most common cause is hormonal changes during puberty. Hormones are chemical messengers that carry instructions to different parts of the body, telling them what to do and when. Once adolescent males are through puberty (within about 2 years), the gynecomastia usually goes away on its own.

• Be sure your healthcare provider knows all medicines and supplements that your child takes. Some can cause gynecomastia, and your healthcare provider may recommend stopping them.
• Sometimes kids feel embarrassed about gynecomastia. Talk to your child about what gynecomastia is, and reassure them that it should go away on its own.
• Your child may want to wear loose-fitting or thicker shirts that can help make gynecomastia less noticeable. If your child is overweight, talk to your healthcare provider about helping your child lose weight. Sometimes losing a little bit of weight will help make the gynecomastia less noticeable.
• Follow your healthcare provider's recommendations for making any follow-up appointments.

• The gynecomastia is getting worse or doesn't go away within 2 years.
• Your child has a lot of pain in the breasts.
• Your child is very upset by the gynecomastia.

What are the signs and symptoms of gynecomastia? Gynecomastia causes breast enlargement, typically in young males. It can happen in one or both breasts. Sometimes a small, rubbery lump can be felt under the nipple. The breast area might feel sore, especially in the months after gynecomastia begins.

What causes gynecomastia? Hormonal changes during puberty cause adolescent males to get gynecomastia.

Some medicines, drugs (including alcohol, marijuana, amphetamines, and heroin), and anabolic steroids (taken to build muscle and improve strength) also can cause gynecomastia. Rarely, gynecomastia can be a sign of other medical conditions.

There's also a condition called pseudogynecomastia (or false gynecomastia). This isn't caused by hormonal changes but rather from extra fat in the chest area. Healthcare providers can usually tell the difference by doing a physical exam.

What is the treatment for gynecomastia? Usually gynecomastia goes away on its own once a male finishes puberty. If gynecomastia is very severe, there is medicine that can help. And if gynecomastia lasts past puberty, surgery can make the breasts smaller.