The healing of anal fissures takes 3-7 days, or even longer. The cause of anal fissures is mainly due to excessively dry and hard stool, which causes fissures in the mucosa of the rectum and anal canal during forceful defecation. Clinically, anal fissures are divided into acute and chronic phases, as follows: a. Acute anal fissures: acute anal fissures are usually treated conservatively and can be cured of clinical symptoms. conservative treatment measures are mainly to eat more fresh vegetables and fruits and other high-fiber foods, so as to keep the stool loose and fluent, take oral lactulose to soften the stool, avoid eating too greasy, spicy and stimulating food, and locally use 1 5000 potassium permanganate sitz bath. Generally, for very superficial fissures, the healing time is very short, maybe 3-5 days. For deeper anal fissures, it may take about a week to heal completely. Chronic anal fissures: For chronic anal fissures, surgical excision is usually required to obtain a cure, and if the fissure is deeper and lasts longer, even the internal anal sphincter needs to be cut to obtain a cure. For chronic anal fissures, it takes a week or more for the local wound to heal clinically through surgical excision.