A 28-year-old woman with end-stage renal disease secondary to diabetes mellitus and hypertension underwent cadaver renal transplant in April 1992. After surgery, she developed bilateral breast enlargement while she was taking cyclosporine for immunosuppression therapy and felodipine, a calcium channel blocker, for blood pressure control. She underwent bilateral reduction mammoplasty in June 1995 to treat progressive breast enlargement which interfered with her normal life activities. Through mechanisms only partially understood, calcium channel blockers and cyclosporine are reported to increase the serum prolactin level, producing gynecomastia in men. There is no report in current literature to support a similar phenomenon in women.