What Is an Anal Fissure?

An anal fissure (anal tear) is a small tear or crack in the skin of the anal canal, which is the area where the large intestine ends and opens to the outside. It commonly causes pain during bowel movements and a few drops of blood when wiping. It is a frequent condition and often mistaken for hemorrhoids.

Anal fissures can occur at any age and are equally common in men and women. In about 85–90% of cases, they appear along the posterior midline (back part of the anus), while 10–15% occur in the front midline. Rarely, they can appear on both sides. Fissures located outside the midline (on the right or left sides) may be associated with other intestinal diseases (e.g., Crohn’s disease) and require further evaluation.

What Are the Symptoms of an Anal Fissure?

Typical symptoms include:

  • A sharp, cutting pain during defecation, followed by throbbing pain that can last from a few minutes to several hours.

  • A few drops of bright red blood on toilet paper or dripping into the toilet.

  • No significant discomfort outside bowel movements.

Many patients develop fear of defecation and delay it due to pain, which makes the stool harder as water is reabsorbed in the rectum — worsening the fissure and pain.
In chronic cases, skin tags (small folds of tissue) can be felt at the edge of the tear.

Non-Surgical Treatment

  • High-fiber diet (vegetables and fruits) to maintain soft, well-formed stools.

  • Stool softeners to ease defecation.

  • Adequate water intake (8–10 glasses daily) to prevent stool hardening.

  • Warm sitz baths or showers for 10–15 minutes, especially after bowel movements, to relax the anal muscles and relieve pain.

  • Topical anesthetic creams to reduce pain.

  • Topical muscle relaxant creams to relieve spasm and promote healing.

What Causes Anal Fissure?

Anal fissures are usually caused by hard stools or excessive straining, leading to small tears in the anal lining.
Rarely, they can occur after diarrhea or frequent bowel movements.

The pain triggers spasm of the anal muscles, which restricts blood flow to the area and delays healing.
Each painful bowel movement worsens the spasm, creating a vicious cycle that leads to a chronic, non-healing wound.
The main goal of treatment is to break this cycle.

Fissures may be acute (new) or chronic (lasting more than 8–12 weeks).
Acute fissures appear as a simple tear, while chronic ones have thickened, raised edges and may be accompanied by scar tissue, skin tags, or internal swelling (hypertrophic papilla).

Because symptoms resemble hemorrhoids, diagnosis is often delayed — turning acute fissures into chronic ones.
Other diseases like infection, cancer, ulcerative colitis, Crohn’s disease, syphilis, tuberculosis, leukemia, or HIV/AIDS can mimic fissures, so proper examination is crucial.

How Is Anal Fissure Treated?

Surgery is not always necessary.
The first goal is to ensure soft, formed stools by adjusting diet and hydration.
Fiber intake of 25–35 grams per day, along with stool softeners and hydration, is recommended.
Pain-relieving creams and warm baths help ease discomfort after bowel movements.
Narcotic painkillers are avoided as they can worsen constipation.

Most acute fissures heal with these measures before becoming chronic.
For chronic fissures, topical creams that relax the anal sphincter may be prescribed.
If these fail, surgical options are considered depending on examination findings and patient preferences.

Can Anal Fissures Recur?

Yes.
Even after complete healing, fissures may recur following hard bowel movements.
To prevent recurrence, patients should maintain regular bowel habits and a fiber-rich diet.
If fissures recur despite these measures, further investigation (e.g., colonoscopy) may be required.

What If the Fissure Does Not Heal?

Persistent fissures should be re-evaluated.
Hard or watery stools, scar tissue, or muscle spasm can delay healing.
Conditions such as inflammatory bowel disease or infection may mimic fissures.

If symptoms persist, additional diagnostic procedures such as colonoscopy or detailed rectal examination under anesthesia may be necessary.

Surgical Options for Anal Fissure

1. Botulinum Toxin (Botox®) Injection

Botulinum toxin is injected into the internal anal sphincter, relaxing the muscle and promoting healing.

  • Healing occurs in 50–80% of cases.

  • The procedure can be done under anesthesia or in specialized proctology units.

  • Recurrence occurs in up to 40% of patients.

  • A second injection or lateral internal sphincterotomy may be needed.

  • Rarely, temporary or mild long-term weakness of anal control may occur.

2. Lateral Internal Sphincterotomy

A controlled partial incision of the internal anal sphincter muscle effectively relieves spasm and pain, allowing healing.

  • Reported success rates exceed 90%.

  • When performed by an experienced surgeon, recurrence is rare (5–10%).

  • Minor gas or stool leakage can occur in some cases.

  • Overall, patients’ quality of life improves significantly compared to those living with chronic fissures.

Recovery Period

Most patients return to work and daily activities within a few days.
Complete healing after surgical or non-surgical treatment takes 6–10 weeks.
Maintaining soft stools, hydration, and fiber intake is crucial.
Persistent spasm or scar formation can delay recovery.

  • Botox®: Heals 50–80% of chronic fissures; recurrence up to 40%.

  • Sphincterotomy: Heals over 90% of cases; recurrence 5–10%; rare risk of mild incontinence.

Do Anal Fissures Cause Colon Cancer?

No.
However, persistent symptoms (such as bleeding) require proper evaluation.
Since fissures share symptoms with other diseases, colonoscopy may be recommended to rule out colorectal cancer or other underlying conditions.