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Anal Itching

(Pruritus Ani)


Parswa Ansari

, MD, Hofstra Northwell-Lenox Hill Hospital, New York

Last full review/revision Feb 2021| Content last modified Feb 2021
Click here for the Professional Version
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Itching of the anus (the opening at the end of the digestive tract where stool leaves the body) and the skin around the anus (perianal skin) is called anal itching or pruritus ani.

Causes of Anal Itching

The most common causes of anal itching are

  • Unknown (the majority)

  • Related to hygiene

Most often, doctors do not identify a specific disorder as the cause of anal itching, and the itching goes away without treatment after a period of time. Many of the other cases of anal itching are due to hygiene issues. Only a very few cases are caused by a specific disorder (see Table: Causes and Features of Anal Itching), such as pinworms or a fungal infection. Of the specific causes, only rare causes such as inflammatory bowel disease and cancer of the skin around the anus are considered serious.

Extremes in hygiene can lead to anal itching. For instance, inadequate cleansing leaves irritating stool and sweat residue on the anal skin. More commonly, overly vigorous cleansing, often with sanitary wipes and strong soaps, can dry or irritate the skin or occasionally cause an allergic reaction. Hemorrhoids can make it difficult for people to thoroughly clean themselves after a bowel movement. Some hemorrhoids produce mucus or cause leakage, both of which can cause itching.

Young children and older people may have problems controlling their urine (called urinary incontinence) or stool (called stool incontinence in children and fecal incontinence in adults). These disorders may cause irritation that leads to skin infections and anal itching.

Once anal itching starts, an itch-scratch-itch cycle can begin, in which scratching causes more itching. Often, people scratch and rub the itchy area so much that they scrape the skin open. The scrapes sometimes become irritated, which causes yet more itching. Also, people sometimes become allergic to the ointments or other treatments they use for the itching.

Evaluation of Anal Itching

Not every episode of anal itching requires immediate evaluation by a doctor. The following information can help people decide whether a doctor’s evaluation is needed and help them know what to expect during the evaluation.

Warning signs

In people with anal itching, certain symptoms and characteristics are cause for concern. They include

  • Pus draining from the anus or around it (draining fistula)

  • Bloody diarrhea

  • Bulging or protruding hemorrhoids

  • Perianal skin soiled with fecal material

  • Dull or thickened perianal skin

When to see a doctor

People who have anal itching plus bloody diarrhea or draining pus should see a doctor in a day or two. Other people should see a doctor if the itching has lasted for more than a few days, but the visit is not urgent.

What the doctor does

Doctors first ask questions about the person's symptoms and medical history. Doctors then do a physical examination. What they find during the history and physical examination often suggests a cause of the itching and the tests that may need to be done (see Table: Causes and Features of Anal Itching).

The history is focused on when the itching started and how long it has lasted. Doctors ask about the following:

  • Ingestion of irritating foods, particularly acidic or spicy foods

  • Bowel habits, including use of wipes, ointments (even those used to treat itching), sprays, and soaps applied to the anus

  • Hygiene habits, particularly frequency of showers and baths

  • Known infections or disorders (such as diabetes, hemorrhoids, or psoriasis)

  • Recent use of antibiotics

The physical examination is focused on the appearance of the anus and the perianal skin. Doctors examine this area for

  • Dullness and thickness

  • Signs of irritation due to scratching

  • Hemorrhoids, lesions, fistulas, and scrapes (caused by scratching and rubbing)


Causes and Features of Anal Itching


Common Features*


Anal or rectal disorders

Discharge of pus

Pain in the rectum (sometimes) and/or abdomen (often)

Sometimes diarrhea

Examination of the lower portion of the large intestine, the rectum, and the anus with an endoscope (sigmoidoscopy) or of the entire large intestine (colonoscopy)

Hemorrhoids (internal or external)

With internal hemorrhoids, bleeding (a small amount of blood on toilet paper or in the toilet bowl)

With external hemorrhoids, a painful, swollen lump on the anus

A doctor's examination

Usually examination of the rectum with an endoscope (anoscopy) or sigmoidoscopy


Bacterial infection (caused by scratching)

Inflamed, red area, sometimes visible scratching

A doctor's examination

Yeast infection (Candida)

A rash around the anus

A doctor's examination

Sometimes examination of a sample of skin scrapings under a microscope (to identify the fungus)

Usually in children

Sometimes present in several family members

Microscopic examination of transparent tape that was applied to the anal area to check for pinworm eggs

Intense itching, usually worse at night

Possibly itching of other body areas

Possibly pink, thin, slightly raised lines or bumps (burrows) on the affected areas

A doctor’s examination

Examination of skin scrapings

Cancer of the skin around the anus (perianal skin)

Scaly or crusty area

Examination of a tissue sample (biopsy)

Skin disorders

An itchy, red, oozing, and crusty rash

A doctor’s examination

Sometimes itchy or painful patches on the skin

A doctor's examination



Current or recent use of an antibiotic

Elimination of the drug to see whether symptoms are relieved

Foods and dietary supplements

Beer, caffeine, chocolate, hot peppers, milk products, nuts, tomato products, citrus fruits, spices, or vitamin C tablets

Symptoms that occur after a substance is ingested

Elimination of the substance from the diet to see whether symptoms are relieved

Hygiene-related problems

Excessive sweating described by the person, particularly with wearing of tight and/or synthetic clothing

Measures to limit sweating (such as wearing loose cotton underwear and changing underwear frequently) to see whether symptoms are relieved

Overly meticulous or aggressive cleansing of the anal area

Poor cleansing

Inappropriate cleansing practices described by the person

A change in cleansing practices to see whether symptoms are relieved

Skin irritants

Anesthetic preparations, ointments, soaps, and sanitary wipes

Use of a possibly irritating substance described by the person

Avoidance of the substance to see whether symptoms are relieved

* Features include symptoms and the results of the doctor's examination. Features mentioned are typical but not always present.


If doctors do not see any abnormalities on or around the anus, they usually do not do tests and simply treat the person's symptoms. If there are any visible skin abnormalities, doctors may examine a scraping of the perianal skin to rule out a fungal infection. Sometimes they give the person a local anesthetic and remove a small piece of tissue to examine under a microscope (skin biopsy).

If pinworms, which most often occur in school-age children, are suspected, eggs can be collected from the anal region using sticky transparent tape to confirm the diagnosis (see diagnosis of pinworm infection).

Doctors may also examine the anus with a short, rigid tube (a procedure called anoscopy) to check for internal hemorrhoids.

Treatment of Anal Itching

  • Treatment of cause

  • Hygiene and symptom relief

The best way to treat anal itching is to treat the underlying disorder. For example, drugs can be taken for parasitic infections (such as pinworms), and creams can be applied for fungal infections (such as Candida, also called yeast).

Irritating foods can be eliminated from the diet or avoided for a while to see whether the itching lessens. If possible, antibiotics can be stopped or switched.

Hygiene and symptom relief

Proper hygiene is important. After bowel movements, the anal area should be cleaned with absorbent cotton or plain soft tissue moistened with warm water or a commercial cleanser made specifically for hemorrhoids. People should avoid using soaps and premoistened wipes.

Frequent dusting with nonmedicated cornstarch or talcum powder helps combat excess moisture.

Corticosteroid ointments (such as 1% hydrocortisone) often help relieve symptoms.

Clothing should be loose, and bed clothing should be lightweight.

Key Points about Anal Itching

  • Pinworms in children and hygiene-related issues in adults are common causes of anal itching.

  • Foods and detergents or soaps can cause anal itching.

  • Appropriate hygiene practices (careful but gentle cleansing, avoiding strong soaps and chemicals, and decreasing skin moisture) can help relieve symptoms of anal itching.

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