The purpose of this clinical phase I study is to measure the efficacy and side effects of Common Sage in the treatment of hot flashes in 10 patients with prostate cancer who receive androgen deprivation (AD) (exclusively or as part of a multimodality treatment) for a period of minimum 6 months. Concomitant use of a non-steroidal anti-androgen during the first month of the AD is permitted to prevent the flair-up phenomenon. However, the inclusion of patients in the study will only start at least 2 weeks after the cessation of the anti-androgen. This is done to exclude a possible influence of the anti-androgen on the severity and frequency of hot flashes.