Botulinum toxin promoted healing and relieved symptoms of chronic anal fissure.

Main results At 1 and 2 months, more patients allocated to botulinum toxin than to placebo had healed fissures (p=0.05 at 1 month and p=0.003 at 2 months) and symptomatic relief (p=0.003 for both 1 and 2 months follow up) (table). 4 patients who still had fissures were retreated with botulinum toxin, 25 U, and all achieved complete healing within 2 months of rescue treatment. No relapses occurred among patients in the botulinum toxin group during a mean follow up of 16 months. 10 patients in the control group received botulinum toxin, 20 U each, and 3 patients underwent sphincterotomy at 2 months. No relapses occurred after rescue treatment in the control group during a mean follow up of 18 months.