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Anal fissure

An anal fissure is a narrow tear that extends from the muscles that control the anus (anal sphincter) up into the anal canal. These tears usually develop when anal tissue is damaged during a hard bowel movement or when higher-than-normal tension develops in the anal sphincters.

Symptoms of an anal fissure include a sharp, stinging, or burning pain during a bowel movement. The pain, which can be severe, may last a few hours. You may also notice spots of bright red blood on toilet tissue. This blood is separate from the stool.

Minor anal fissures can often be helped to heal by drinking more fluids, eating a high-fiber diet, allowing enough time for a bowel movement, and using stool softeners.

  • Symptoms

    What are the symptoms of an anal fissure?

    The symptoms of an anal fissure may include:

    • A sharp, stinging, or burning pain during bowel movements. Pain from a fissure may be quite severe. It can be brief or last for several hours after a bowel movement.
    • Itching.
    • Bleeding. You may see a small spot of bright red blood on toilet tissue or a few drops in the toilet bowl. The blood from a fissure is separate from the stool. (Very dark, tarry stools or dark red blood mixed with stool may be a sign of a more serious problem.) Tell your doctor if you have any bleeding with a bowel movement.

    Sometimes an anal fissure may be a painless wound that won't heal. It may bleed from time to time but cause no other symptoms.

  • Causes

    What causes an anal fissure?

    Anal fissures are caused by injury or trauma to the anal canal. Injury can happen when:

    • You pass a large stool.
    • You are constipated and try to pass a hard stool.
    • You have repeated diarrhea.
    • You give birth. (Childbirth can cause trauma to the anal canal.)

    Fissures can also be caused by a rectal exam, anal intercourse, or a foreign object. In some cases, a fissure may be caused by Crohn's disease.

    Many experts believe that extra tension in the two muscular rings (sphincters) controlling the anus may be a cause of fissures. The outer anal sphincter is under your conscious control. But the inner sphincter is not. This muscle is under pressure, or tension, all of the time. If the pressure increases too much, it can cause spasm and reduce blood flow to the anus, leading to a fissure. This pressure can also keep a fissure from healing.

  • Diagnosis

    How is an anal fissure diagnosed?

    A doctor can diagnose an anal fissure based on your symptoms and a physical exam. The exam may include:

    • Looking at the fissure by gently separating the buttocks.
    • A digital rectal exam. The doctor inserts a gloved finger into the anal canal.
    • Anoscopy. This involves using a short, lighted scope to look into the anal canal.

    The doctor may wait until the fissure has started to heal before doing a rectal exam or anoscopy. If an exam needs to be done right away, medicine can be used to numb the area.

    During an exam, a doctor can also find out whether another condition may be causing the fissure. Having several fissures or having one or more in an area of the anus where fissures usually don't occur can be a sign of a more serious problem, such as inflammatory bowel disease or a weakened immune system.

  • Treatment

    How is an anal fissure treated?

    About 9 out of 10 short-term fissures heal with home treatment-including using stool softeners or fiber supplements and taking regular sitz baths. And about 4 out of 10 long-term anal fissures will heal after home treatment is used.

    But not all fissures will heal with just home treatment. If a fissure lasts more than 8 to 12 weeks, you may need prescription medicines. These may include nitroglycerin cream, high blood pressure medicines in pill or gel form, or injections of botulinum toxin (Botox).

    If medicines don't stop your symptoms, you may need to consider surgery. The most commonly used surgery is lateral internal sphincterotomy. In this procedure, a doctor cuts into part of the internal sphincter to relax the spasm that is causing the fissure.

  • When to call

    Anal fissure: When to call

    Call your doctor now or seek immediate medical care if:

    • You have new or worse pain.
    • You have new or worse bleeding from the rectum.

    Watch closely for changes in your health, and be sure to contact your doctor if:

    • You have trouble passing stools.
    • You do not get better as expected.
  • Self-care

    How can you care for an anal fissure?

    • If your doctor prescribed cream or ointment, use it exactly as prescribed. Call your doctor if you think you are having a problem with your medicine. You will get more details on the specific medicines your doctor prescribes.
    • Sit in a few inches of warm water (sitz bath) 3 times a day and after bowel movements. The warm water helps the area heal and eases discomfort. Do not put soaps, salts, or shampoos in the water.
    • Avoid constipation:
      • Include fruits, vegetables, beans, and whole grains in your diet each day. These foods are high in fiber.
      • Drink plenty of fluids, enough so that your urine is light yellow or clear like water. If you have kidney, heart, or liver disease and have to limit fluids, talk with your doctor before you increase the amount of fluids you drink.
      • Get some exercise every day. Build up slowly to 30 to 60 minutes a day on 5 or more days of the week.
      • Take a fiber supplement, such as Benefiber, Citrucel, or Metamucil, every day if needed. Read and follow all instructions on the label.
      • Use the toilet when you feel the urge. Or when you can, schedule time each day for a bowel movement. A daily routine may help. Take your time and do not strain when having a bowel movement. But do not sit on the toilet too long.
    • Support your feet with a small step stool when you sit on the toilet. This helps flex your hips and places your pelvis in a squatting position.
    • Your doctor may recommend an over-the-counter laxative, such as Miralax, Milk of Magnesia, or Ex-Lax. Read and follow all instructions on the label, and do not use these medicines on a long-term basis.
    • Do not use over-the-counter ointments or creams without talking to your doctor. Some of these preparations may not help.
    • Use baby wipes or medicated pads, such as Preparation H or Tucks, instead of toilet paper to clean after a bowel movement. These products do not irritate the anus.
    • Be safe with medicines. Read and follow all instructions on the label.
      • If the doctor gave you a prescription medicine for pain, take it as prescribed.
      • If you are not taking a prescription pain medicine, ask your doctor if you can take an over-the-counter medicine.

    Copyrighted material adapted with permission from Healthwise, Incorporated. This information does not replace the advice of a doctor.