Drug-Induced Gynecomastia: A Systematic Review and Meta-Analysis of Randomized Clinical Trials

This systematic review and meta-analysis of 32 randomized controlled trials examined the risk of drug-induced gynecomastia in patients taking spironolactone, antiandrogens, 5 alpha-reductase inhibitors, lipid-lowering, and psychotropic drugs. The findings revealed significantly increased odds of gynecomastia in men using antiandrogens (OR = 17.38) and 5 alpha-reductase inhibitors (OR = 1.77), as well as in mixed-gender populations using spironolactone (OR = 8.39). No placebo-controlled trials were available for antipsychotic drugs, but risperidone showed higher odds of gynecomastia compared to quetiapine (OR = 4.32). The increased risk is likely due to alterations in the testosterone to estradiol ratio and elevated prolactin levels associated with certain antipsychotics. Limited evidence was found regarding the effects of statins on mammary glands.