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Gynecomastia
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Gynecomastia

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Gynecomastia is hypertrophy of breast tissue in males.

During puberty, enlargement of the male breast is normal. It is usually transient, bilateral, smooth, firm, and symmetrically distributed under the areola; breasts may be tender. Similar changes may occur during old age but are more often unilateral. Most of the enlargement is due to proliferation of stroma, not of breast ducts.

Gynecomastia may be caused by various disorders (especially hepatic and renal failure; less commonly, endocrine disorders), drugs (eg, anabolic steroid abuse, antineoplastic drugs, Ca channel blockers, cimetidine Some Trade Names
TAGAMET
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, digitalis, estrogens Some Trade Names
PREMARIN
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, isoniazid Some Trade Names
INH
NYDRAZID
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, ketoconazole Some Trade Names
NIZORAL
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, methadone Some Trade Names
DOLOPHINE
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, metronidazole Some Trade Names
FLAGYL
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, reserpine Some Trade Names
SERPASIL
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, spironolactone Some Trade Names
ALDACTONE
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, theophylline Some Trade Names
ELIXOPHYLLIN
THEO-DUR
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), and marijuana.

Gynecomastia is rarely confused with cancer, which is asymmetric, hard, and often fixed to dermis or fascia. Usually, the only imaging or other diagnostic test needed is mammography.

In most cases, no specific treatment is needed because gynecomastia usually remits spontaneously or disappears after any causative drug (except perhaps anabolic steroids) is stopped or underlying disorder is treated. If cosmetic appearance is unacceptable, surgical removal of excess breast tissue (eg, suction lipectomy alone or with cosmetic surgery) may be used.

Last full review/revision November 2005

Content last modified November 2005

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