Nifedipine for local use in conservative treatment of anal fissures : Preliminary results of a multicenter study

This study was performed according to a prospective, randomized, double-blind, multicenter design. The aim was to test the efficacy of local application of nifedipine gel" in healing acute anal fissure by relaxing the internal anal sphincter. Two hundred eighty-three patients who gave informed consent were recruited; they received a clinical examination. A questionnaire to evaluate the symptoms and the pain was administered, and a proctoscopy and anorectal manometry were performed. Patients treated with nifedipine (n = 141) used topical 0.2 percent nifedipine gel every 12 hours for three weeks. The control group, consisting of 142 patients, received topical 1 percent lidocaine and 1 percent hydrocortisone acetate gel during therapy. Manometry was performed before and on Days 14 and 21. Anal pressures were measured by recording resting and squeeze pressures. Results obtained were as follows: total remission from acute anal fissure was achieved after 21 days of therapy in 95 percent of the nifedipine-treated patients (P < 0.01), as opposed to 50 percent of the controls (P < 0.01), and previously elevated maximum resting anal pressures decreased from a mean value +/- standard deviation of 72.5 +/- 10.07 mmHg to 50.5 +/- 10.03 mmHg in the nifedipine group. This represents a mean reduction of 30 percent (P < 0.01). We also observed a significant decrease in squeeze pressures in nifedipine-treated patients (from a mean +/- standard deviation of 130.5 +/- 19.25 mmHg to 108.5 +/- 18.55 mmHg, a mean reduction of 16.8 percent; P < 0.01). No changes in anal pressures were observed in the control group. We did not observe any systemic side effect or significant anorectal bleeding in patients treated with nifedipine. Our study clearly demonstrates that the therapeutic use of nifedipine, which at present is used only in cardiovascular pathologies, should be extended with local use to the conservative treatment of anal fissures.