Most anal fissures heal on their own within six weeks using simple home treatments: more fiber, warm soaks, and keeping stools soft. A fissure is a small tear in the lining of the anal canal, usually caused by passing hard or large stools. The pain can be sharp and intense, but the condition is common and highly treatable at every stage.
Why Fissures Take Time to Heal
When a tear forms in the anal lining, the ring of muscle surrounding it (the internal sphincter) tends to tighten in response to the pain. That tightness reduces blood flow to the area, which slows healing. The tear then causes more pain during bowel movements, the muscle tightens further, and the cycle continues. Every effective fissure treatment works by breaking this loop, either by softening stool so it passes with less trauma, relaxing the sphincter muscle, or both.
A fissure that persists beyond six weeks is classified as chronic. Chronic fissures often develop thickened edges or a small skin tag near the tear, and they’re less likely to resolve without medical treatment. The sooner you address a fissure with basic care, the better your odds of avoiding that transition.
Home Treatments That Work
The goal of first-line treatment is straightforward: softer stools and a relaxed sphincter. These measures heal the majority of acute fissures without any medication.
Fiber: Aim for 25 to 30 grams of fiber per day from food, supplements, or a mix of both. Fruits, vegetables, legumes, and whole grains all count. If your current intake is low, increase gradually over a week or two to avoid bloating. Drink plenty of water alongside the fiber, since fiber absorbs fluid and needs it to soften stool effectively.
Sitz baths: Sitting in a few inches of warm water for 15 to 20 minutes relaxes the sphincter muscle and increases blood flow to the area. Three to four sitz baths a day is a common recommendation, especially after bowel movements when pain peaks. You can use a shallow basin that fits over your toilet seat or simply fill a bathtub partway. No soap or additives are needed.
Stool management: If fiber alone isn’t producing soft, easy-to-pass stools, a lubricant like mineral oil (one tablespoon with a meal) can help stools move through with less friction. Don’t combine mineral oil with stool softeners, and limit use to a few days at a time since it can interfere with vitamin absorption. The key is keeping stools soft without tipping into diarrhea, which can irritate a healing fissure just as much as hard stool can.
Avoid straining during bowel movements. Go when you feel the urge rather than delaying, and don’t sit on the toilet longer than necessary.
Prescription Creams for Chronic Fissures
When a fissure doesn’t heal after six weeks of home care, topical medications are the standard next step. These creams work by chemically relaxing the internal sphincter, restoring blood flow so the tear can close.
Two main options exist. Nitroglycerin ointment (applied at a low concentration to the anal area twice daily) has been used for decades. It’s effective, healing about 76% of chronic fissures in studies, but it causes headaches in a large share of users. In one head-to-head trial, 46% of patients using nitroglycerin reported headaches.
Diltiazem cream, a calcium channel blocker, works just as well, healing roughly 80% of chronic fissures over six weeks. The major advantage is tolerability: only 14% of patients experienced headaches. Because of this better side-effect profile, clinical guidelines from the American Society of Colon and Rectal Surgeons support using calcium channel blockers as a first-line topical treatment over nitroglycerin.
Both creams are typically applied twice daily for eight weeks. You continue the fiber and sitz baths alongside them. The creams don’t require a prescription in every country, but in the U.S. they’re usually compounded by a pharmacy with a doctor’s order.
Botulinum Toxin Injections
If topical creams fail, injections of botulinum toxin directly into the sphincter muscle offer another non-surgical option. The toxin temporarily paralyzes a small portion of the muscle, reducing its tightness and allowing the fissure to heal. The procedure is quick and done in an office or outpatient setting.
Success rates are moderate. In a study of 91 patients, 60% achieved healing after injection. That’s somewhat lower than surgery, but the procedure carries less risk of long-term side effects. Clinical guidelines note that botulinum toxin provides modest improvement in healing when used as a second-line therapy after topical creams have failed. The relaxing effect is temporary, lasting a few months, so recurrence is possible.
When Surgery Becomes the Best Option
For chronic fissures that haven’t responded to creams or injections, a procedure called lateral internal sphincterotomy is the gold standard. The surgeon makes a small, controlled cut in the internal sphincter muscle to permanently reduce its resting tension. This restores blood flow and lets the fissure heal.
The procedure has a 95% success rate in curing chronic fissures, making it far more effective than any non-surgical approach. It can be done as an outpatient procedure, and recovery typically involves a few weeks of mild discomfort. Long-term complications are rare, estimated at less than 5%, and the most discussed concern, some degree of difficulty controlling gas or stool, is uncommon and usually minimal when it does occur. Surgeons now tailor the length of the cut to match the fissure itself, which has reduced incontinence risk compared to older techniques.
Surgery can also be offered to patients who haven’t tried medications first, particularly when the fissure is clearly chronic and the patient wants the most reliable path to healing. For patients who have underlying sphincter weakness or prior continence issues, an alternative called an anocutaneous flap uses a small piece of nearby skin to cover the fissure. It carries comparable healing rates with even lower risk to sphincter function.
What Recovery Looks Like
For acute fissures treated at home, most people notice pain improvement within days of softening their stool, with full healing taking four to six weeks. The sharp pain during bowel movements is usually the first symptom to ease.
Chronic fissures treated with creams take longer. Expect to use the medication for a full eight-week course before judging whether it worked. Some people feel better within two to three weeks but should continue the cream for the recommended duration to prevent relapse.
After surgery, the fissure pain often improves dramatically within the first week, though the surgical site itself needs a few weeks to fully heal. Sitz baths and fiber remain important during this period.
Preventing Recurrence
Fissures come back when the conditions that caused them return. The single most important preventive measure is maintaining soft, bulky stools long-term. That means keeping fiber intake at 25 to 30 grams daily and staying well hydrated as permanent habits, not just temporary fixes during a flare.
Avoid prolonged sitting on the toilet, which increases pressure on the anal canal. If you’re prone to constipation, address it early rather than waiting for stools to become hard and difficult to pass. Regular physical activity also supports healthy bowel function. For people who’ve had multiple recurrences despite good habits, a follow-up to discuss whether the sphincter muscle remains abnormally tight can help guide whether additional treatment is worthwhile.