What You Need to Know About Anal Fissures
Dr. Kam Ming Hian
MBBS (Singapore), M.Med (Surgery)

Senior Consultant,
Colorectal Surgeon

An anal fissure is a small tear or crack in the lining of the anus, the opening through which stool is expelled from the body. It is characterized by a burning pain, itchy sensation and rectal bleeding during and after a bowel movement. The condition affects all age groups, but it tends to be found when constipation and diarrhea are frequent.

By itself, anal fissures are not serious, and they usually heal on their own within a few weeks. Some, however, are chronic and more serious, and may require medicines and even surgery to treat. Persistent anal fissures may also be an indication of an underlying illness such as inflammatory bowel diseases, cancer or sexually transmitted diseases (STDs).

  • Causes and Symptoms of Anal Fissures

    Anal fissures commonly occur from straining during bowel movements when passing large or hard stools. Similarly, chronic constipation and diarrhea may place excessive pressure on the anal canal, causing it to stretch and tear. Other causes of anal fissures include:

    • Childbirth
    • Inserting foreign objects into the anus
    • Anal intercourse
    • Poor blood flow to the anus
    • Tight or spastic anal sphincter muscles

    In some cases, anal fissures are symptoms of a more complex illness such as anal cancer, leukemia, ulcerative colitis, Crohn’s disease, HIV, syphilis and herpes.

    Anal fissures may be easily detected by sight or touch, but symptoms are more noticeable during and after a bowel movement. These include:

    • Sharp pain when passing stools, followed by a burning sensation
    • Bright red blood present on the stools or toilet paper
    • Itching, which can be persistent or recurrent

    Anal fissures may also be painless, but still take a long time to heal and may bleed occasionally.

    There are patients who try to delay bowel movements in order to prevent the painful anal fissure from flaring up. However, this further increases the risk of constipation with larger and harder stools, which make them even more difficult to expel.

  • Risk Factors of Anal Fissures

    Certain factors make some people more prone to developing anal fissures. These include:

    • Age – It is observed that many infants develop anal fissures, though the reason remains unclear. In adults, the occurrence can be attributed to decreased blood supply to the anal region because of poor circulation.
    • Childbirth – Women are more susceptible to anal fissures after giving birth.
    • Constipation – Sitting on the toilet for too long or excessive straining during bowel movements can cause the anal canal to stretch and tear.
    • Diarrhea – On-going diarrhea causes the anal canal to become dry, making it prone to tearing.
    • Anal intercourse – Trauma sustained during these sexual activities can result in anal fissures.
  • Complications of Anal Fissures

    Although an anal fissure is not a life-threatening condition, it does come with complications that can affect overall quality of health and life. These are:

    • Inability to heal – Most anal fissures heal by themselves in a week or two, but in some instances, they don’t. These are considered chronic fissures that require medical or surgical intervention.
    • Recurrence – Anal fissures can return after healing.
    • Anal stricture – The presence of scar tissue or a spastic anal sphincter may cause the anal canal to become narrow, which impedes the regular passage of stools.
    • Sentinel pile and fibroepithelial polyps – There may excessive growth of skin around the anus externally, often due to the repeated attempts at healing. This is usually a sign that the anal fissure is chronic.
  • Treatment for Anal Fissures

    Most cases of anal fissures can be treated at home with stool softeners and sitz baths, and simple diet and lifestyle modifications. These include sticking to a high-fiber diet to avoid constipation, keeping hydrated during the day and not straining or sitting on the toilet for a prolonged period. Some anal fissures also heal on their own in one to two weeks, even without treatment.

    If the anal fissures still do not improve after two weeks, you should seek medical attention.

    Initially, topical and anesthetic creams may be given to reduce pain and inflammation. Nitroglycerin ointments are also commonly prescribed to relax the sphincter, improve blood supply to the anal area and encourage healing. To treat a spastic anal sphincter, botulinum toxin injections can help lessen spasms by immobilizing the sphincter muscle.

    Surgery is the best option to treat severe anal fissures that are not responsive to diet and lifestyle changes and medications. A method called lateral anal sphincterotomy (LAS) is typically performed, in which a small portion of the sphincter muscle is removed to prevent pain and spasms.

  • Prevention of Anal Fissures

    The steps taken to prevent anal fissures are similar to the steps taken to avoid constipation. They include:

    • Eating high-fiber food
    • Drinking plenty of fluids
    • Exercising regularly
    • Cleaning the anal area and keeping it dry
    • Changing diapers frequently (for infants)

    While anal fissures cannot always be avoided, simple diet and lifestyle modifications can greatly reduce one’s risk of developing it more often.

    Kam Colorectal Centre offers comprehensive and highly effective anal and colorectal surgery services to address conditions such as hemorrhoids, anal fissures, diverticular disease and cancer. Book an appointment today with Dr Kam by calling 6443-1005.