Topical Metronidazole (10 Percent) Decreases Posthemorrhoidectomy Pain and Improves Healing

INTRODUCTION: Oral metronidazole has been previously demonstrated to decrease postoperative pain after open diathermy hemorrhoidectomy. The current study investigates the efficacy of topical metronidazole (10 percent) in reducing postoperative pain and promoting wound healing after Harmonic Scalpel hemorrhoidectomy. METHODS: A prospective, randomized trial was conducted to compare posthemorrhoidectomy pain and wound healing with use of topical metronidazole (10 percent) vs. placebo carrier, applied to the surgical site. Surgical indications included grade 3 or 4 internal or external hemorrhoidal disease, with or without a fissure-in-ano. Pain was assessed using a visual analog score (VAS) preoperatively and on postoperative days 1, 2, 7, 14, and 28. Twenty-four-hour narcotic use (hydrocodone 10 mg) was recorded on postoperative days 1, 2, 7, 14, and 28. Digital photographs of the surgical site were taken at 14 days postoperatively. The photographs were independently ranked by three blinded observers according to a) postoperative edema, b) primary vs. secondary healing, and c) overall wound healing. RESULTS: Twenty patients were randomized in a prospective manner, ten to the topical 10 percent metronidazole group and ten to the placebo carrier group. Patients in the topical metronidazole group experienced significantly less postoperative pain at day 7 (VAS +/- SEM, 3.4 +/- 0.4 vs. 6.3 +/- 0.5; P = 0.002) and day 14 (1.0 +/- 0.4 vs. 3.2 +/- 0.7, P = 0.02). There was no statistical difference in narcotic analgesic requirements between groups. In the metronidazole group, postoperative edema was ranked significantly lower (mean score, 3.0 vs. 7.0, P < 0.01) and overall wound healing ranked significantly better (4.0 vs. 7.0, P = 0.03) than in controls. CONCLUSION: Topical 10 percent metronidazole significantly reduces posthemorrhoidectomy discomfort at days 7 and 14 postoperatively. Postoperative edema is reduced and overall healing is improved, compared with that of carrier controls.