Osteoporosis and long-term androgen suppression in the treatment of paraphilias has been documented with surgical castration and the use of gonadotropin-releasing hormone agonists. The literature has suggested that the use of cyproterone acetate (CPA) may be protective against osteoporosis, although there are case reports of osteoporosis in men treated with CPA. This pilot study represents a case series of seven patients diagnosed with severe paraphilias and treated with CPA, leuprolide, or surgical castration. Two of the four patients treated with CPA developed significant osteoporosis, while the other two had normal bone density studies. The remaining three patients, one treated with leuprolide and two with surgical castration, had osteopenia. Based upon the current literature, the finding of significant osteoporosis in two of four patients treated with CPA, but not those treated with leuprolide or castration, is surprising. Monitoring of all patients treated with long-term androgen suppression for osteoporosis is suggested.