The effect of topical nifedipine in treatment of chronic anal fissure.

Chronic anal fissure is the most common cause of anal pain associated with internal anal sphincter hypertonia. Reduction of hypertonocity is a special treatment for fissure healing. For this purpose chronic anal fissures were conventionally treated by anal dilatation or by lateral sphincterotomy. However, both of these methods may cause a degree of incontinence in some patients. The uptake of medical therapies that create a reversible chemical sphincterotomy has recently become widespread. The aim of this prospective clinical trial study was to assess the effectiveness of nifedipine in healing anal fissure, a calcium channel blocker that reduces sphincter pressure. A single-blind randomized comparative trial was setup to compare traditional treatment with stool softeners and 2% lidocaine cream against 0.5% nifedipine cream for 4 weeks. 110 patients were included in this study, 60 patients in the nifedipine group and 50 patients in the control group and the therapeutic outcome and side effects were recorded. Healing had occurred in 70% of patients in the nifedipine group and in 12% of patients in the control group after 4 weeks treatment (P < 0.005). Recurrence of symptoms occurred in four of healed patients in the nifedipine group and three patients in the control group in two months. The final result of nifedipine application after 12 months follow up was recurrence in 11 patients (26.19%). Mild headache occurred in four patients (6.6%) of the nifedipine group. Patients in the nifedipine group showed significant healing and relief from pain compared with patients in the control group. Recurrence rate with nifedipine use in spite of control of predisposing factors such as constipation was significant. Another finding was low complication rate with this treatment.