Anal fissure

DEFINITION

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An anal fissure is a small tear in the thin, moist tissue (mucosa) that lines the anus. An anal fissure may occur when you pass hard or large stools during a bowel movement. Anal fissures typically cause pain and bleeding with bowel movements. You also may experience spasms in the ring of muscle at the end of your anus (anal sphincter).

Anal fissures are very common in young infants but can affect people of any age. An anal fissure usually heals on its own within four to six weeks. If it doesn’t, medical treatment or surgery usually can relieve discomfort.

CAUSES

Common causes of anal fissure include:

• Passing large or hard stools
• Constipation and straining during bowel movements
• Chronic diarrhea
• Inflammation of the anorectal area, caused by Crohn’s disease or another inflammatory bowel disease
• Childbirth

Less common causes of anal fissures include:

• Anal cancer
• HIV
• Tuberculosis
• Syphilis
• Herpes

SYMPTOMS

Signs and symptoms of an anal fissure include:

• Pain, sometimes severe, during bowel movements
• Pain after bowel movements that can last up to several hours
• Bright red blood on the stool or toilet paper after a bowel movement
• Itching or irritation around the anus
• A visible crack in the skin around the anus
• A small lump or skin tag on the skin near the anal fissure

When to see a doctor

See your doctor if you have pain during bowel movements or notice blood on stools or toilet paper after a bowel movement.