An anal fissure is a small split or tear in the thin moist tissue (mucosa) lining the lower rectum (anus).
Fissure in ano
Anal fissures are very common in infants, but they may occur at any age. The rate of anal fissures drops with age. Fissures are much less common among school-age children than in infants.
In adults, fissures may be caused by passing large, hard stools, or having diarrhea for a long time. Other factors may include:
Decreased blood flow to the area in older adults
Too much tension in the sphincter muscles that control the anus
Anal fissures are also common in women after childbirth and in persons with Crohn's disease.
Anal fissures may cause painful bowel movements and bleeding. There may be blood on the outside of the stool or on the toilet paper (or baby wipes) after a bowel movement.
Symptoms may begin suddenly or develop slowly over time.
Other symptoms may include:
A crack in the anal skin that can be seen when the area is stretched slightly (the fissure is almost always in the middle)
Exams and Tests
The health care provider will perform a rectal exam and look at the anal tissue.
Most fissures heal on their own and do not need treatment.
To prevent or treat anal fissures in infants, be sure to change diapers often and clean the area gently.
CHILDREN AND ADULTS
Worrying about pain during a bowel movement may cause a person to avoid them. But not having bowel movements will only cause the stools to become even harder, which can make anal fissure worse.
Prevent hard stools and constipation by:
Making dietary changes -- eating more fiber or bulk, such as fruits, vegetables, and grains
Drinking more fluids
Using stool softeners
Applying the following ointments or creams to the area may soothe the skin:
Numbing cream, if pain interferes with normal bowel movements
Zinc oxide, 1% hydrocortisone cream, Preparation H, and other products
A sitz bath is a warm water bath used for healing or cleansing. You should sit in the bath two to three times a day. The water should cover only your hips and buttocks.
If the anal fissures do not go away with home care methods, treatment may involve:
Botox injections into the muscle in the anus (anal sphincter)
Minor surgery to relax the anal muscle
Prescription creams such as nitrates or calcium channel blockers, applied over the fissure to help relax the muscles
Anal fissures usually heal quickly without any more problems.
People who develop fissures once are more likely to have them in the future.
Marcello PW. Diseases of the anorectum. In: Feldman M, Friedman LS, Brandt LJ, eds. Sleisenger and Fordtran's Gastrointestinal and Liver Disease. 9th ed. Philadelphia, PA: Elsevier Saunders; 2010:chap 125.
Perry WB, Dykes SL, Buie WD, et al. Practice parameters for the management of anal fissures (3rd revision). Dis Colon Rectum. 2010;53:1110-1115.
Stafford SL, Klein MD. Anorectal malformations. In: Kliegman RM, Stanton BF, St. Geme JW III, et al., eds. Nelson Textbook of Pediatrics. 19th ed. Philadelphia, PA: Elsevier Saunders; 2011:chap 336.1.
John A. Daller, MD, PhD, Department of Surgery, University of Arkansas for Medical Sciences, Little Rock, AR. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.