A significant proportion of men undergoing transrectal ultrasound (TRUS) and prostate biopsy report pain during the procedure. A number of different methods of pain relief have been suggested in the literature. We prospectively evaluated the effect of diclofenac suppositories on pain experienced by men undergoing TRUS and prostate biopsy. A prospective, randomized, double-blind, placebo controlled study was performed in 72 patients requiring prostate biopsy. Patients were randomly assigned to receive 100 mg diclofenac or placebo 1 hour prior to the procedure. They were asked to indicate on a 10 cm visual analogue scale the degree of discomfort during the procedure. The patients were then seen 2 weeks later and any morbidity, including infection and bleeding, was assessed. Patients given diclofenac had significantly lower pain scores than those given placebo (2.8 vs 4.9, p <0.001). The 2 groups were similar in regard to age, prostate volume, biopsy number, prostate specific antigen, histological diagnosis and complication rate. Rectal administration of diclofenac 1 hour prior to TRUS and prostate biopsy is a simple procedure that significantly relieves the pain experienced with no increase in morbidity. With the trend toward more core samples, screening for prostate cancer and the younger age of patients undergoing biopsy we urge urologists to provide analgesia for this painful procedure.