What are the aims of this leaflet?
This leaflet has been written to help you understand more about pruritus ani. It will tell you what it is, what causes it, what can be done about it, and where you can find out more about it.
What is pruritus ani?
‘Pruritus’ means itching. Pruritus ani is itching around the opening of the back passage (the anus). It is a symptom with many causes, but sometimes no obvious cause can be found. Pruritus ani is common and occurs more often in men than women. It is seldom due to an underlying serious condition and those who have pruritus ani are usually otherwise well.
What causes pruritus ani?
Pruritus ani has many possible causes, so it is sensible to seek the advice of your doctor if you experience itching around the anus.
Some of the more common causes are:
Anal disease.The contents of the bowel contain digestive enzymes that can irritate the skin and cause itching. Minor leakages of bowel motions, and a failure to remove them completely from the skin around the anus when wiping, can lead to pruritus ani. One contributory factor may be the presence of piles (haemorrhoids), which are the result of build-up of pressure on the blood vessels of the anal area. Constipation (not opening the bowels regularly) can make the piles and pruritus ani worse. Skin tags (small skin growths) in the anal area can also contribute to itching.
Skin disease around the back passage.Examples of this include psoriasis, eczema, thrush (a Candida yeast infection), and fungal infections.
Threadworms.In children, itching around the back passage is often due to threadworms, which can cause pruritus ani in adults too. The itching is usually worse at night.
Allergy.Pruritus ani may be due to an allergy to something in contact with the skin, for instance to fragrance in toilet paper, or to local anaesthetics or preservatives in creams used for piles.
Skin irritation.The skin of the bottom is sensitive and can easily be irritated by moist tissue wipes, soaps, perfumes, antiseptics (for example, Dettol). These make the skin sore and itchy, and contribute to pruritus ani.
Sweating.The skin around the back passage is often moist with sweat. If long periods pass without ventilation to the area, for instance if you sit down for a long time or wear tight underwear, the skin can be irritated further and become itchy.
Is pruritus ani hereditary?
What are the symptoms of pruritus ani?
Itching is the main symptom, often occurring after the bowels have opened. Itching may be experienced during the night interfering with sleep. Sometimes the skin becomes sore and can crack or ‘fissure’ after scratching, making it uncomfortable to open your bowels.
What does pruritus ani look like?
The skin around the anus may look inflamed and thickened, and show scratch marks. Small fissures may occur and these may feel painful and sensitive, and bleed.
How is pruritus ani diagnosed?
It is usually possible to make a diagnosis of pruritus ani by hearing your story and examining the affected skin. Your doctor will want to find out why you have pruritus ani, and may need to examine you for threadworms, allergies etc. The tests selected will depend on the clues offered by your story and the examination of the skin around the anus.
Can pruritus ani be cured?
As there are so many different causes of pruritus ani, there is no one treatment that can cure all cases. It is important to have a correct diagnosis to ensure the right treatment can be implemented to relieve the symptom of itching.
How can pruritus ani be treated?
The first step will be to find out if any of the causes listed above are playing a part in causing your pruritus ani. If they are, then your doctor will treat them appropriately.
If no obvious cause can be found, your doctor may suggest a variety of ways of helping such as:
A short course of a steroid ointment or cream to be applied every day to the area to reduce the itching. This can then be used as and when needed should pruritus ani return.
A course of antihistamine may be prescribed by your doctor to relieve itching.
It is important to remove all irritants such as bowel motions or soap from the skin creases. An emollient cream, such as aqueous cream, should be used instead of soap for washing the area to avoid the irritating effect of soap and detergents. Cotton wool balls with warm water are gentler than toilet paper and more effective in cleaning fissures and skin creases. It is important to ensure no little bits of toilet paper or cotton wool are left in the area as this will cause more irritation. The area also should be rinsed thoroughly after you have opened your bowels.
If you have troublesome constipation, you should see your family doctor for advice.
CAUTION: This leaflet mentions ‘emollients’ (moisturisers). When paraffin-containing emollient products get in contact with dressings, clothing, bed linen or hair, there is a danger that a naked flame or cigarette smoking could cause these to catch fire. To reduce the fire risk, patients using paraffin-containing skincare or haircare products are advised to avoid naked flames completely, including smoking cigarettes and being near people who are smoking or using naked flames. It is also advisable to wash clothing and bed linen regularly, preferably daily.
Self care (What can I do?)
You should avoid any of the things listed above that might be contributing to your pruritus ani. If you notice that a particular food makes the itching worse, avoid it.
Scratch as little as possible, as scratching keeps the itch going.
Open your bowels regularly. Try not to delay going to the toilet when you have the urge to do so.
Keep your stools soft so you do not have to strain to open your bowels. Eat plenty of fruit, vegetables and other roughage, and drink plenty of water.
The use of a bidet or a shower jet helps to remove particles of bowel motion that have become trapped near the anus. Always dry the skin gently, without rubbing it.
Keep the area as well ventilated as possible. Underwear should be loose and made of cotton not synthetic materials. Avoid prolonged sitting.
Avoid getting too hot in bed at night and avoid wearing underwear in bed.
Where can I get more information?
Web links to detailed leaflets:
For details of source materials used please contact the Clinical Standards Unit (firstname.lastname@example.org).
This leaflet aims to provide accurate information about the subject and is a consensus of the views held by representatives of the British Association of Dermatologists: individual patient circumstances may differ, which might alter both the advice and course of therapy given to you by your doctor.
This leaflet has been assessed for readability by the British Association of Dermatologists’ Patient Information Lay Review Panel
BRITISH ASSOCIATION OF DERMATOLOGISTS
PATIENT INFORMATION LEAFLET
PRODUCED AUGUST 2004
UPDATED MAY 2010, MAY 2013, JUNE 2016
REVIEW DATE JUNE 2019