An acute anal fissure typically heals within 6 weeks with conservative treatment. Some disappear when constipation is treated. Anal fissures that last for 6 weeks or more are called chronic anal fissures. These fail conservative treatment and need a more aggressive, surgical approach.
People whose anal fissures don’t heal well may have an imbalance in anal pressure that prevents blood from circulating normally through the blood vessels around the anus. The reduced blood flow prevents healing. Medicine, Botox injections, and even some topical treatments that improve blood flow, may help anal fissures heal.
Other treatments include:
Changing your diet to increase fiber and water, steps that will help regulate your bowel movements and reduce both diarrhea and constipation
Taking warm baths for up to 20 minutes a day
Taking stool softeners, such as fiber supplements, as needed
Using topical medicines, such as nitrates or calcium blockers
Having surgery, such as a lateral internal sphincterectomy. During the surgery, the pressure inside the anus is released. This allows more blood to flow through the area to heal and protect tissues.
The risks from Botox injections and medicines used to treat anal fissures are relatively mild. Complications from surgery include the risk for infection, bleeding, and persistent gas and fecal incontinence, or uncontrolled bowel movements.