Anal pain

Pain coming from the bottom area is not something that we are used to feeling and, as a consequence, anal pain can cause a lot of worries.

What sort of pain is it?

• A knife-like pain when you have your bowels open, and which may last for 10–15 minutes afterwards, is probably caused by an anal fissure. Some people describe it as like ‘passing glass’. In addition to the pain, you may notice some bright red blood on the toilet paper.
• A similar knife-like pain can be caused by herpes simplex virus.
• A nagging, aching discomfort made worse by defecation could be due to piles.
• A throbbing pain, worsening over a few days, and bad enough to disturb your sleep, is likely to be caused by an abscess.
• An occasional, severe, cramp-like pain deep in the anal canal, lasting about half an hour, is probably a condition called proctalgia fugax.
• A continuous aching pain in the anus needs to be sorted out by your doctor. It is most often caused by a back problem (when a part of the spine presses on a nerve).

Anal fissure
An anal fissure is a split in the anal skin, just inside the anus, usually towards the back. The pain of an anal fissure feels like being cut with glass when you have your bowels open and afterwards. It is worse when you have had a hard bowel motion. You may notice some bright red blood on the lavatory paper at the same time. You may be able to feel a small lump alongside the crack; this is a ‘skin tag’.

Anal fissures are most common in teenagers and young adults, and there has often been a period of constipation beforehand. Sometimes they follow childbirth. They usually heal on their own, but this often takes several weeks and the scar may split again.

What you can do. Do not feel anxious about the fissure. Although it is horribly painful, it is not a dangerous condition.

• Avoid constipation – this is very important. Keep your faeces soft by eating lots of bran cereals, fruit and vegetables.
• Smear some painkilling gel around the area just before you have your bowels open. You can buy a suitable painkilling gel from a pharmacy; they are sometimes labelled ‘for piles’ or ‘for haemorrhoids’. It will prevent the anus going into a spasm, which can make the problem worse. Do not use the gel at any other time, or for more than 1 week, because you can easily develop an allergy to its ingredients. If you notice soreness and itching, in addition to the sharp pain, it is quite likely that the gel is responsible.
• Warm baths twice daily can help, if you have the time. Put a handful of ordinary kitchen salt into the bath.

How your doctor can help. You should see your doctor if the problem is not improving after 3 weeks. If you feel anxious about this, look at the section on seeing your doctor about an anal problem. For some treatments, your doctor will need to send you to the ‘rectal clinic’ at your local hospital. Some of the treatments your doctor may use are listed below.

• Glyceryl trinitrate ointment, applied several times a day for 6 weeks, seems to heal the fissure in 60–70% of cases. However, about 50% of the people using this treatment get a headache as a side effect.
• A gel containing the drug diltiazem is being tried in some hospitals. It can help people who do not respond to glyceryl trinitrate.
• Some specialist hospitals have been using injections of botulinum toxin (Botox) into the muscle of the anus. Botulinum toxin prevents spasm of the muscle, because it blocks transmission of nerve impulses to the muscle. This treatment is not widely available. Healing rates are about 69–90%, but it needs more research to see how effective it is in the long term.
• The most common treatment (before glyceryl trinitrate ointment came on the scene) used to be a small operation under a general anaesthetic. The operation is designed to overcome the spasm of the anal muscle. The pain relief is dramatic and instantaneous. In the past, this operation could leave you less able to control wind, but a new type of operation (tailored sphincterotomy) does not have this drawback (British Journal of Surgery 2005;92:403–8).

Unfortunately, the fissure comes back within 3–4 months in about one-third of people treated with glyceryl trinitrate or diltiazem, and in about 40% of people after treatment with botulinum toxin (Gastroenterology 2002;123:112–7). Surgery seems to be the best long-term cure and is effective in about 90% of cases.

Herpesvirus infection
A herpesvirus infection can produce a pain similar to an anal fissure. Herpes can infect the anal area, either spread by the hands from a cold sore on the face, or transmitted as a sexual infection. At the anus, herpes often forms a crack rather than the small ulcers that tend to occur elsewhere. It can occur in individuals who have never had herpes elsewhere. The soreness occurs in episodes, each lasting for a few days. A genitourinary medicine clinic will be able to take a swab to check for the virus if you visit the clinic as soon as an episode starts; if you are worried about the thought of visiting a clinic, take a look at the section on visiting the clinic.

Abscess
An abscess close to the anus produces a throbbing pain that worsens over a few days, and is usually bad enough to disturb your sleep. You may be able to feel a tender swelling in the skin beside the anus, or the abscess may be hidden inside. This is unlikely to go away on its own; it needs to be lanced by a doctor.

Proctalgia fugax
Proctalgia fugax is a severe, cramp-like pain, deep in the anal canal. It usually lasts for less than a minute, but can sometimes last for up to half an hour. Most sufferers have only 5 or 6 attacks a year. You may feel a need to defecate urgently, but nothing happens. It may even make you feel dizzy, or give you a headache. It occurs in both men and women. The pain often wakes sufferers at night, and men may have an erection at the same time. Some men experience it after sex. It is a mysterious condition; no one knows what causes it, but it is probably a spasm of the rectal or pelvic floor muscles and does not mean that you have anything seriously wrong. There are various methods of relieving the pain.

• Try putting pressure on the perineum (the area between the back passage and the vagina or base of the penis) by sitting on the edge of your bath or on a tennis ball.
• Sit in hot water or, alternatively, apply some ice.
• Two paracetamol tablets and a hot drink may give some relief.

The problem with medications for proctalgia fugax is that the episode is likely to be over before the drugs become active. They might be worth trying if your attacks last a long time. Possible treatments are glyceryl trinitrate spray or under-the-tongue tablets (as used for angina), glyceryl trinitrate cream applied to the anal area, or the asthma drug salbutamol (inhaled from a puffer at the start of the attack). These treatments are only available on prescription, for which you would need to see your doctor.

• Seeing your doctor about an anal problem
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