一些藥物的副作用也可以，例如胃藥西米替丁

Medications

A number of medications can cause gynecomastia. These include:

• Anti-androgens used to treat an enlarged prostate, prostate cancer and other conditions. Examples include flutamide, finasteride (Proscar, Propecia) and spironolactone (Aldactone, Carospir).
• Anabolic steroids and androgens, which are prescribed by doctors for certain conditions or are sometimes used illegally by athletes to build muscle and enhance performance.
• AIDS medications. Gynecomastia can develop in men who are HIV-positive and receiving a treatment regimen called highly active antiretroviral therapy. Efavirenz (Sustiva) is more commonly associated with gynecomastia than are other HIV medications.
• Anti-anxiety medications, such as diazepam (Valium).
• Tricyclic antidepressants.
• Antibiotics.
• Ulcer medications, such as the over-the-counter drug cimetidine (Tagamet HB).
• Cancer treatment.
• Heart medications, such as digoxin (Lanoxin) and calcium channel blockers.
• Stomach-emptying medications, such as metoclopramide (Reglan).