Asymmetric, Tender Gynecomastia Induced by Olanzapine in a Young Male

Sir, Approximately 10–25% of the causes of gynecomastia are drug‐induced.[1] Gynecomastia may result from imbalance in levels of androgen and estrogen as well as the elevated level of prolactin.[2] Drugs involving these hormone systems are likely to cause gynecomastia. Antipsychotic medications‐induced hyperprolactinemia may manifest as gynecomastia.[3] Antipsychotic medications such as clozapine, olanzapine, aripiprazole, ziprasidone, and quetiapine possess prolactin‐sparing property, hence the risk of gynecomastia with these medications is low.[3‐5] The evidence for olanzapine‐induced gynecomastia are scarce and limited to case reports.