Unilateral Gynecomastia Induced by Treatment With 1 mg of Oral Finasteride
March 2001
in “
Archives of Dermatology
”
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TLDR Finasteride can cause one-sided breast enlargement, which disappears after stopping the drug.
This document reports on four cases of unilateral gynecomastia induced by treatment with 1 mg of oral finasteride, a drug commonly used to treat male pattern hair loss. The breast enlargement disappeared between 2 to 10 months once use of the drug was discontinued. The authors suggest that new studies are needed for better knowledge of the real incidence of this adverse effect of the drug.