What is an anal fissure?
An anal fissure is a tear in the skin that covers the anus. The tear may extend into the internal anal sphincter (IAS), which is a circular ring of muscle that surrounds the anus. Anal fissures are called acute if you’ve had them for less than six weeks or chronic if you’ve had them for more than six weeks.
How many people have anal fissures?
Some studies estimate that one in five people will develop a fissure during their lifetime. Some doctors think the real number may be higher since some people are too embarrassed to talk about their anal fissures.
What causes anal fissures?
The most common cause of anal fissures is trauma from passing hard stools. Most fissures heal quickly without any treatment. However, some get worse and require treatment.
When you get a fissure, the pain causes the internal anal sphincter to go into spasm. This increases the resting pressure in the anus. That reduces blood supply (ischemia) to the area. The poor blood flow to the area makes it difficult for the fissure to heal. A vicious cycle starts that may cause the tear to grow larger, increasing the pain and making things worse. To make things worse, you still have to defecate. Feces also slow the healing. Worse, the pain causes some people to become afraid to defecate making them constipated. Hard stools also worsen the fissures. As you can see, the vicious cycle is a never-ending one. The goal of treatment is to disrupt this vicious cycle and allow the fissure to heal.
Hard stools, childbirth, and diarrhea can all cause or worsen fissures. In rare cases, fissures can be caused by another disease such as Crohn’s disease or anal herpes. In these rare cases, you will have other symptoms that point to the particular disease. The chances that your fissures are caused by any of these rare diseases is very small. So don’t worry about them. Besides, your doctor will evaluate you to make sure a rare disease isn’t involved. This handout focuses on the majority of anal fissures that aren’t caused by a rare disease.
What are the symptoms of anal fissures?
Bleeding: A small amount of bright red blood may be present. It is usually limited to the toilet paper and perhaps the surface or the cracks of a hard stool. However, you may also find some blood in the toilet bowl.
Pain: Pain and the sensation of tearing or burning after a bowel movement is usually present. This may feel like passing “shards of glass”. These symptoms usually occur after every bowel movement, may be very severe, and may last several minutes to an hour after a bowel movement.
Itching: Some anal fissures may cause itching.
How are anal fissures diagnosed?
Your doctor will usually diagnose an anal fissure based on your symptoms. That diagnosis is confirmed by doing an anal examination.
How are anal fissures treated?
The goal of treatment is to break the vicious cycle of pain leading to spasm and ischemia (see figure 1), prevent further tearing of the anal skin, and promote healing of the fissure. We do this by 1) Reducing constipation and softening your stools, and 2) Relaxing the internal anal sphincter to reduce spasm and pain, 3) Keeping the area clean to avoid irritation.
1) High fiber diet: Increase dietary fiber and water intake to soften and bulk the stool. The recommended dietary fiber intake is between 20 and 35 grams per day.
2) Drink lots of water: Drink at least 2 Liters or 67 ounces per day. That is eight 8-oz glasses of water.
3) Fiber supplements: If you are is still passing hard stools after dietary fiber and increased water intake, take either psyllium husk (Metamucil), or methylcellulose (Citrucel), or wheat dextran (Benefiber), or calcium polycarbophil (Fibercon). Take as directed.
4) Stool softener: If your stool is still too hard, take a stool softener.
5) Sitz bath: Do warm sitz baths of about 10 to 15 minutes 2-3 times per day plus after each bowel movement to relax the anal sphincter and improve blood flow to the anal mucosa. This will facilitate healing. Get Sitz bath kit or portable bowl from a drugstore. A bathtub may be used for a sitz bath by filling it with 2-3 inches of warm water and adding Epsom salt. Don’t add soap and bubble bath. Wipe thoroughly but gently with a towel or blow dry after each sitz bath.
6) Balneol (Main ingredients: Water, mineral oil, propylene glycol, and lanolin oil.) – Use as needed for cleansing after bowel movements.
7) Prescription Medications: Your doctor will prescribe topical medications to help promote blood flow and facilitate healing of the anal fissure.
8) Surgery: If symptoms don’t resolve after the above options have been exhausted, surgery may be indicated.
Diagram from: Madalinski, Mariusz H. “Identifying the Best Therapy for Chronic Anal Fissure.” World Journal of Gastrointestinal Pharmacology and Therapeutics 2.2 (2011): 9–16.