Mesalazine (5-Aminosalicylic Acid) Suppositories in the Treatment of Ulcerative Proctitis or Distal Proctosigmoiditis: A Randomized Controlled Trial

Abstract
A multicentre double-blind study was conducted to evaluate the efficacy and tolerability of 1 g or 1.5 g mesalazine daily compared with placebo in 94 patients with mild to moderate distal proctosigmoiditis (<20 cm). The study end point was the determination of clinical, endoscopic, and histologic remission rates at 4 weeks. Eleven patients, nine receiving placebo and two receiving 1.5 g mesalazine, withdrew during trial, mostly because of worsening of symptoms. At 4 weeks clinical remission was achieved in 7 of 31 (39%) patients with placebo, in 22 of 32 (69%) patients in the 1g mesalazine group, and 23 of 31 (74%) patients in the 1.5 g mesalazine group. No serious clinical or biochemical side effect of treatment was reported. Mesalazine suppositories are safe, well tolerated, and very effective in patients with active distal proctosigmoiditis; 500 mg twice daily appears a suitable dose regimen.