Anal itching (pruritus ani) is a sensation of itching, burning or irritation around the anus. It is quite common and most of the time does not arise from a serious disease.
There may nevertheless be a treatable cause behind long-standing or recurrent itching, such as haemorrhoids, skin disease, infection or leakage of stool.
What are the commonest causes of anal itching?
The area staying damp
Sweat, remnants of stool, or the leakage of very small amounts of stool can irritate the skin around the anus.
Itching may be more common in people who have diarrhoea or a problem with faecal incontinence in particular.
Excessive cleaning
People with anal itching sometimes begin to clean the area more. Soap, shower gel, perfumed products and wet wipes can, however, irritate the sensitive skin further.
Washing frequently and drying vigorously can also disturb the skin’s natural protective layer and lead to more itching.
A cycle can thus form: itching → more cleaning → more irritation → more itching.
Do haemorrhoids cause itching?
Yes, they can.
External haemorrhoids in particular, or internal haemorrhoids that prolapse outwards, can cause dampness, mucus and irritation around the anus.
Not everyone with anal itching has haemorrhoids, however. It is not right to put the itching down to haemorrhoids without an examination.
Can an anal fissure cause itching?
An anal fissure is a small tear that forms in the anal canal.
Although its most typical symptom is a sharp pain during and after opening the bowels, burning, itching and a small amount of bright red bleeding can also be seen.
Do parasites cause anal itching?
Yes; threadworm (Enterobius vermicularis) in particular can cause anal itching.
It is typical for the itching to become marked at night. Although it is commoner in children, it can also occur in adults.
Not every case of anal itching in adults is due to a parasite, however.
For this reason it is not right to take an anti-parasitic medicine indiscriminately simply because there is itching.
Can fungal and other infections cause itching?
Fungal and certain other infections around the anus can cause itching and redness.
The area staying constantly damp, diabetes, and certain conditions affecting the immune system in particular can make it easier for infection to develop.
Using an antifungal cream continually without a diagnosis is not appropriate.
Can skin diseases cause anal itching?
Yes.
Eczema, contact dermatitis, psoriasis and certain other dermatological diseases can affect the area around the anus.
Finding similar skin changes elsewhere on the body can help in the diagnosis.
Do foods cause anal itching?
Some people notice that coffee, alcohol, spicy foods or certain acidic foods increase their symptoms.
It is not right, however, to give every patient a long list of forbidden foods.
It is a more appropriate approach for the person to cut down the foods they have noticed markedly increase their own symptoms.
What helps anal itching?
In most patients the first aim is to reduce irritation of the skin around the anus and to keep it dry.
The following may help:
- Cleaning the area gently
- Avoiding perfumed soaps and shower gels
- Not using wet wipes unnecessarily
- Drying the area after washing without rubbing
- Avoiding tight clothing that does not let the skin breathe
- Preferring cotton underwear
- Trying not to scratch
- Treating the cause of any diarrhoea or leakage of stool
In some patients a suitable barrier cream can be used to protect the skin from stool and moisture.
The indiscriminate long-term use of creams containing steroids, antibiotics or antifungals is not appropriate, however.
Why does scratching make things worse?
Scratching creates small areas of damage in the skin.
Damaged skin becomes more irritated and begins to itch more. Continual scratching can over time cause the skin to thicken and the itching to become chronic.
One of the important aims of treatment is therefore to break the itch–scratch cycle.
Can anal itching be a sign of cancer?
Cancer is not the cause of most anal itching.
Rarely, however, certain diseases of the anal region or its surroundings can present with long-standing itching.
Where the itching is accompanied by:
- Bleeding
- A sore that will not heal
- A lump that can be felt
- Discharge
- Marked pain
- Unexplained weight loss
in particular, examination is important.
When should a doctor be consulted?
Assessment is appropriate in the following situations:
- Itching that has been going on a long time
- Severe itching, or itching that recurs continually
- Bleeding from the back passage
- Pain or swelling
- Discharge
- A sore or skin change around the anus
- Faecal leakage or constant dampness
- A new change in bowel habit
- No improvement despite the simple measures taken
How is the cause of anal itching established?
In most cases a detailed history and examination of the anal region is the most important step.
Anoscopy or rectal examination can be carried out where required. Where a parasite, an infection or a skin disease is suspected, the relevant investigations can be requested.
Colonoscopy is not needed for every case of anal itching. The need for colonoscopy is assessed separately according to the patient’s age, bowel symptoms, bleeding and other risk factors.
Remember
Anal itching does not always mean haemorrhoids or a parasite.
Sometimes the problem is quite the opposite: cleaning the area more than necessary, and the irritant products used on it.
In long-standing or recurrent itching, rather than merely suppressing the itch, it is sounder to establish the cause and treat that.
Sources
- Prof. Ali Tüzün İnce, MD