sentences:  Also, women who are sexually active and who can or may become pregnant should use an effective method of contraception to prevent pregnancy while taking an antiandrogen.Antiandrogens are often combined with birth control pills for this reason, which can result in additive efficacy.The FDA-mandated black-box warning about tumorigenic potential of spironolactone, as it may increase certain tumors, which has been shown in animal studies, and the caution that "Unnecessary use of this drug should be avoided."