Like other small cuts or tears to the skin, an anal fissure will often heal by itself within a few weeks.
However, you should see a GP if you have an anal fissure as they can give you advice and medicines to help ease your symptoms and allow the fissure to heal more quickly.
Most anal fissures will heal with treatment, although they can happen again easily, particularly if you do not follow self-help advice.
There are a number of self-help measures the GP may recommend to relieve constipation and reduce the pain caused by anal fissures.
Relieving constipation can allow anal fissures to heal and reduce the chance of further fissures developing in the future.
Self-help measures include:
- increasing your daily intake of fibre by including plenty of high-fibre foods in your diet, such as fruit, vegetables and wholegrains
- avoiding dehydration by drinking plenty of water
- trying to get more exercise – for example, by going for a daily walk or run
- working out a place and time of day when you can comfortably spend time on the toilet
- not delaying going to the toilet when you feel the urge
- if you use wet wipes, avoiding products that contain fragrance or alcohol as this could lead to discomfort or itching – if you use toilet paper, use a soft brand and avoid wiping too hard
- soaking your bottom in a warm bath several times a day, particularly after having a poo, to relax the muscles in your anus
See preventing anal fissures for more self-help advice.
There are a number of different medicines a GP may recommend to help reduce your symptoms and allow your anal fissure to heal.
Laxatives are a type of medicine that can help you poo more easily.
Adults with an anal fissure will usually be prescribed bulk-forming laxative tablets or granules. These work by helping your poo retain fluid, making it softer and less likely to dry out.
Children with an anal fissure are usually prescribed an osmotic laxative oral solution. This type of laxative works by increasing the amount of fluid in the bowels, which stimulates the body to need to poo.
A GP may recommend starting treatment at a low dose and gradually increasing it every few days until you're able to pass soft poo every 1 or 2 days.
If you decide to take these medicines, make sure you follow the dosage instructions on the patient information leaflet or packet.
If your symptoms do not improve within a week or 2, the GP may prescribe a medicine called glyceryl trinitrate (GTN), an ointment applied to the anal canal, usually twice a day.
GTN works by expanding blood vessels in and around the anus, increasing the blood supply to the fissure and helping it heal faster. It can also help reduce the pressure in the anal canal, which should ease the pain.
You'll usually have to use GTN ointment for at least 6 weeks, or until your fissure has completely healed.
The majority of acute fissures (present for less than 6 weeks) will heal with GTN treatment. Around 7 in every 10 chronic fissures heal with GTN therapy if used correctly.
Headaches are a very common side effect of GTN ointment, affecting up to half of people who use it. Some people also feel dizzy or lightheaded after using the ointment.
GTN is not suitable for children or pregnant or breastfeeding women.
If headaches are a problem, reducing the amount of ointment you use for a few days can help. Using a pea-sized amount of ointment 5 or 6 times a day is often better than using a larger amount twice a day.
If you have particularly severe anal pain, the GP may prescribe a topical anaesthetic to numb your anus before you have a poo.
A topical medicine is one you rub directly into the affected area. It will not help fissures heal, but it can help ease the pain.
Lidocaine is the most commonly prescribed topical anaesthetic for anal fissures. It comes in the form of either a gel or an ointment, and is usually only used for a short time (a few days).
Calcium channel blockers
However, topical calcium channel blockers that are applied directly to the anus have also proved useful in treating some people with anal fissures.
Topical calcium channel blockers work by relaxing the sphincter muscle and increasing blood supply to the fissure.
Side effects can include headaches, dizziness, and itchiness or burning at the site when you use the medicine. Any side effects should pass within a few days once your body gets used to the medicine.
Topical calcium channel blockers are thought to be about as effective as GTN ointment for treating anal fissures, and may be recommended if other medicines have not helped.
As with GTN ointment, you'll usually have to use calcium channel blockers for at least 6 weeks, or until your fissure has completely healed.
Botulinum toxin injections
Botulinum toxin is a relatively new treatment for anal fissures. It's usually used if other medicines have not helped. Botulinum toxin is a powerful poison that's safe to use in small doses.
If you have an anal fissure, an injection of the toxin can be used to paralyse your sphincter muscle. This should prevent the muscle from spasming, helping reduce pain and allowing the fissure to heal.
It's not clear exactly how effective botulinum toxin injections are for anal fissures, but research suggests they're helpful for more than half the people who have them. This is similar to having treatment with GTN ointment and topical calcium channel blockers.
The effects of botulinum toxin injections last for around 2 to 3 months, which should normally allow enough time for the fissure to heal.
You may have a follow-up appointment a few weeks after starting your treatment. This will allow the GP to check your fissure has healed or is showing adequate signs of improvement.
If the fissure has completely healed, the GP may recommend a further follow-up appointment a few weeks later.
If your anal fissure is particularly severe or does not respond to treatment after 8 weeks, you may have to be referred to a colorectal surgeon, a doctor who specialises in conditions that affect the rectum and anus. This usually involves having some type of surgery.
Surgery may be recommended if other treatments have not worked.
It is generally considered to be the most effective treatment for anal fissures, with more than 9 out of 10 of people experiencing good long-term results. However, it does carry a small risk of complications.
There are a number of different surgical techniques that can be used to treat anal fissures.
A lateral sphincterotomy involves making a small cut in the ring of muscle surrounding the sphincter to help reduce the tension in your anal canal. This allows the anal fissure to heal and reduces your chance of developing any more fissures.
It is a short and relatively straightforward operation that's usually carried out under a general anaesthetic on a day patient basis. This means you'll be asleep while the procedure is carried out, but you will not usually have to spend the night in hospital.
A lateral sphincterotomy is one of the most effective treatments for anal fissures, with a good track record of success. Most people will fully heal within 2 to 4 weeks.
Less than 1 in 20 people who have this type of surgery will experience some temporary loss of bowel control (bowel incontinence) afterwards as a result of damage to the anal muscles.
However, this is usually a mild type of incontinence where the person is unable to prevent farting (flatulence), and usually only lasts a few weeks.
Advancement anal flaps
Advancement anal flaps involve taking healthy tissue from another part of your body and using it to repair the fissure and improving the blood supply to the site of the fissure.
This procedure may be recommended to treat long-term (chronic) anal fissures caused by pregnancy, or an injury to the anal canal.
Page last reviewed: 09 November 2021
Next review due: 09 November 2024