PURPOSE: Anal sphincter spasm is believed to play an important role in pain after hemorrhoidectomy. We tested a different form of nitroglycerin: the Nitroderm TTS(R) band. We investigated its efficacy on posthemorrhoidectomy pain and the relation between pain and anal resting pressure measured preoperatively and postoperatively. METHODS: Thirty-eight hemorrhoid patients were divided into two groups: those with high anal resting pressure were classified as group A (n = 24) and those with low anal resting pressure were classified as group B (n = 14). After hemorrhoidectomy, Nitroderm TTS(R) bands were placed into the anal canal in half of the patients in groups A and B (groups A-1 and B-1) and not in the remaining half (groups A-2 and B-2). Anal resting pressure measurement was repeated at the first dar and third month postoperatively. Postoperative pain was assessed by linear analog scale, and analgesic consumption was recorded. RESULTS: Preoperative anal resting pressure was 112.0 (range, 95-140) cm H2O in group A-1 and 110.6 (range, 96-138) cm H2O in group A-2. The difference was insignificant. However, on the first postoperative day, anal resting pressures were 88.7 (range, 75-115) and 110.9 (range, 92-135) cm H2O (P = 0.0001), and at the third month, they were 76.5 (range, 70-100) and 78.0 (range, 70-105) cm H2O, respectively (P = 0.690). Postoperative pain scores were significantly lower in group A-1 than group A-2 (P = 0.0001). In the low-pressure groups (B-1 and B-2), anal resting pressures before surgery, on the first postoperative day, and at the third month postoperatively were 70.4 (range, 56-76), 67.4 (range, 50-75), and 67.2 (range, 55-74) cm H2O in group B-1 and 69.8 (range, 58-76), 70.2 (range, 60-76), and 68.4 (range, 60-74) cm H2O in group B-2. The differences were insignificant (P greater than or equal to 0.660). The differences between pain scores in these groups were also insignificant (P greater than or equal to 0.160). CONCLUSION: Nitroderm TTS(R) bands effectively reduced anal resting pressure and relieved pain in patients with high preoperative anal resting pressure.