Some men taking a medication may develop gynecomastia.
Criteria for diagnosis of drug-induced gynecomastia:
(1) no evidence of gynecomastia prior to starting an implicated drug
(2) no other explanation for the gynecomastia
(3) improvement after discontinuing drug (may take some time)
Possible mechanisms may include an estrogenic or antiandrogenic effect or hyperprolactinemia.
Drugs associated with gynecomastia include:
(1) amiodarone
(2) androgens
(3) anti-retroviral agents
(4) azoles (ketoconazole, metronidazole)
(5) calcium channel blockers (diltiazem, verapamil, nifedipine, other)
(6) chemotherapeutic/cytotoxic agents (alkylating agents, vincristine, etc)
(7) cimetidine
(8) clomiphene
(9) D-penicillamine
(10) diazepam
(11) digitalis
(12) estrogenic agents
(13) flutamide
(14) human chorionic gonadotropin
(15) isoniazid
(16) methyldopa
(17) phenothiazine (chlorpromazine, other)
(18) phenytoin
(19) reserpine
(20) spironolactone
(21) theophylline
(22) tricyclic antidepressants
Drugs of abuse
(1) methadone
(2) marijuana
(3) anabolic steroids
(4) amphetamines
