Pruritus ani (itchy bottom)

What is pruritus ani?

‘Pruritus’ means itching. Pruritus ani is itching around the opening of the back passage (the anus). It is a common condition occurring more often in men than women.

What does pruritus ani look and feel like?

Itching is the main symptom, often occurring after the bowels have opened. Itching may be experienced during the night, interfering with sleep.

Depending on the cause the skin may look normal, erythematous (pink/red), or hyperpigmented (darker in colour than the surrounding skin). Sometimes the skin becomes sore and can crack or ‘fissure’ after scratching, making it uncomfortable to open your bowels.

What causes pruritus ani?

There are many causes including:

• Minor leakages of bowel motions, and a failure to remove them completely from the skin around the anus when wiping - the contents of the bowel contain digestive enzymes that can irritate the skin and cause itching. One contributory factor may be the presence of piles (haemorrhoids) or skin tags

• 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

• Irritation and contact allergy - the skin around the bottom is sensitive and can easily be irritated by moist tissue wipes, soaps, perfumes and antiseptics. 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 conditions around the back passage e.g. psoriasis and eczema

• Infections e.g. thrush (a Candida yeast infection), bacterial infection, and threadworms (threadworms look like pieces of white thread and can be seen on the faeces). You might also see them around your child's bottom (anus). The worms usually come out at night while your child is sleeping

• Serious bowel disease - bowel cancer is a very uncommon cause, however, should you notice a change in your bowel habit (constipation, diarrhoea, or a change in how often you open your bowels), abdominal pain, or bleeding from the back passage, you must make an urgent appointment to see your GP

• Sometimes, no obvious cause can be found
  

Things you can do to help yourself

• Establish a regular bowel habit (e.g. once a day), keep your stools soft and avoid straining when you open your bowels - this can be achieved by eating plenty of fruit, vegetables and other roughage, and by drinking plenty of water

• It is important to clean your bottom properly after a bowel movement - cotton wool balls with warm water are gentler than toilet paper and may be more effective in cleaning. 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 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 by patting it dry rather than rubbing

• An emollient cream should be used instead of soap for washing the area to avoid the irritating effect of soap and detergents. Some people find that applying a thin layer of a moisturising cream after a bowel motion, when the skin feels itchy, and at bedtime can help; in others it may irritate the skin

• Try to avoid overheating and sweating - keep the area as well ventilated as possible. Underwear should be loose and made of cotton not synthetic materials. Avoid prolonged sitting. Do not wear underwear in bed and avoid getting too hot

• Prevent skin damage - keep nails short. If you feel like you want to scratch your skin find something for your hands to do until the itch passes (e.g. a job around the house or use a stress ball). If you must touch your skin try patting rather than scratching or rubbing (scratching can break the skin, rubbing can causes the skin to thicken, which we call lichen simplex)

• See your pharmacist and ask about emollient creams (moisturisers), and treatments for threadworm if appropriate

Make an appointment at your GP surgery

Make an urgent appointment if there is any suggestion of a more serious cause (as above), otherwise if your itch has not improved with the measures described above then book a routine appointment.

Your health professional may take a skin swab to look for infection or recommend a steroid cream or ointment if the skin looks inflamed. This link provides details on specific treatments.

Referral to a specialist

If your pruritus ani needs investigating, or remains troublesome you will need to be referred to a specialist.

What will happen when you are referred?

If a more serious cause is possible, you will be referred urgently (in England and Wales this will be a ‘2 week wait’ referral).

If there is no suggestion of a serious cause you will be referred routinely. If an allergy is suspected to something contacting the skin, you may require patch testing. Pruritus ani is NOT caused by food allergy.

Can pruritus ani be cured?

If investigations find a cause for the pruritus, treatment of this will sometimes lead to resolution of the itch. If a cause is not found, treatment is about managing the pruritus and keeping the itch to a minimum. In some, pruritus will persist for many years, in others it may resolve spontaneously (of its own accord).

Helping with other skin conditions

If you, a family member, or friend have an undiagnosed skin condition; or you want to learn more about how to treat skin conditions, please view our short video on how to get the best from this website.