produce undervirilization/sexually ambiguous genitalia in male fetuses. due to its teratogenic capacity, contraception should be used in women taking bicalutamide who are fertile and sexually active. skin, fat, and bone skin changes antiandrogen therapy and estrogen therapy are known to produce demasculinizing and feminizing effects in the skin and on hair follicle distribution in people assigned male at birth. androgens are involved in regulation of the skin (e.g., sebum production), and antiandrogens are known to be associated with skin changes. skin-related side effects, which included dry skin, itching, and rash, were reported at a rate of 2% in both monotherapy and cab clinical studies of bicalutamide in men. sensitivity to light a few cases of photosensitivity (hypersensitivity to ultraviolet light-induced skin redness and/or lesions) associated with bicalutamide have been reported. in one of the cases, bicalutamide was continued due to effectiveness in treating prostate cancer in the patient, and in combination with strict photoprotection (in the form of avoidance/prevention of ultraviolet light exposure). eventually, the symptoms disappeared and did not recur. flutamide is also associated with photosensitivity, but much more frequently in comparison to bicalutamide. fat distribution antiandrogen therapy and estrogen therapy are known to produce demasculinizing and feminizing effects on fat distribution in people assigned male at birth. bone density and fractures bicalutamide monotherapy preserves bone mineral density in men with prostate cancer relative to surgical or medical castration. this is considered to be due to preservation of gonadal estradiol production with bicalutamide monotherapy, in contrast to castration which greatly reduces estradiol levels. the risk of osteoporosis and serious bone fractures with bicalutamide monotherapy appears to be no different than with non-use in men with prostate cancer. gastrointestinal system the incidence of diarrhea with bicalutamide monotherapy in the epc trial was comparable to placebo (6.3% vs. 6.4%, respectively). in phase iii studies of bicalutamide monotherapy for lapc, the rates of diarrhea for bicalutamide and castration were 6.4% and 12.5%, respectively, the rates of constipation were 13.7% and 14.4%, respectively, and the rates of abdominal pain were 10.5% and 5.6%, respectively. heart, liver, kidneys, and lungs cardiovascular system