Pruritus ani, also called as anal itching or itchy anus/itchy butt, can cause severe distress and sleep disturbance due to persistent itching. Itching may be so intense that one may avoid all social events and be isolated at home, ruining his/her professional career as well as personal life. One must understand that itchy anus is not a disease, its a symptom caused by several external and internal factors that can be avoided and treated effectively regardless of the cause.
Anal itching can be due to several factors that results in wetness, irritation, inflammation, or trauma to the anal area. In some cases the exact cause may be hard to find and can take longer to diagnose and treat. In most cases it can be due to change in pH and natural protective oils of the anal region. Other causes can just be due to common skin dermatoses or could be the skin manifestation of systemic illness.
In pruritus ani, itching is often localized in the anal region with little or no itching elsewhere. Pruritus ani commonly affects 1-5% of general population and is commonly seen in males of 20-40 years of age then females. Although pruritus ani is not a life threatening and accompanying serious systemic illness is rare, it is often important to do a thorough systemic examination for any malignancies like squamous cell carcinoma and extramammary paget’s disease, so you don’t have to regret later.
Anal Itching Causes
Anal neurodermatitis is one of the causes of itchy anus and is so intense during night that patients may tear the affected area until it bleeds.
Allergic contact dermatitis (ACD)
ACD is another common cause of anal itching. ACD could be due to various agents like fragrances in toilet paper, detergents, bubble baths, preservatives or anything that come in contact with the area.
Irritant contact dermatitis (ICD)
ICD may also cause anal itching. Irritant contact dermatitis may result from repetitive exposure to irritants from gastrointestinal contents, like hot spices or inadequate cleaning of the anal area after bowel moments. Anatomical abnormalities of the anal area or fecal incontinence can also leak rectal irritant to the skin causing irritant contact dermatitis.
Ingestion of contact allergens in certain foods can cause pruritus ani in some individuals, particularly if they are excreted unchanged. These may include Tea, coffee, milk products, cheese, chocolates, nuts, carbonated beverages, tomatoes and tomato products etc. Smoking and alcohol has also been associated with pruritus ani.
Fungal infection is another cause of itchy anus, it may be associated with red/white swollen rash with fissuring around the anal region. Patients with diabetes are more susceptible for perianal candidiasis. In case of female, candidiasis is an important cause and should always prompt screening for diabetes mellitus.
When itching is present in female gonorrhea is also suspected, however it is almost ignored in men, especially when itching is the only symptom.
Although itching is less common, erythrasma involving groin and perianal region may also cause occasional itching.
Seborrheic dermatitis of the anal area may also cause pruritus ani. However, it may also be evident on other areas like inguinal region, scalp, chest and face.
Lichen planus and psoriasis
Sometimes lichen planus and psoriasis can also cause perianal itching but lesion are usually not limited to perianal region, other areas of the body may also be involved.
Pediculosis and Scabies
Pediculosis also causes anal itch, but patient main focus may be on pubic itching. Scabies also can cause anal itching; however itching is not limited to anal area. Itchy lesion in scabies usually involves finger web-space, wrist, axillae and genitals.
Intestinal parasites infestation
Pinworm/threadworm infestation may also cause itchy anus, particularly in children and occasionally in adults. Night anal itching is very common in pinworm infestation in children. Other intestinal parasites may also cause anal itching.
Aggressive cleansing of the anal area
Sometimes over cleaning or aggressive cleaning of the anal area can also result in chronic itchy anus. Its common practise to clean more thinking that poor hygiene might have brought the issue. So the more you clean with scented soaps the worse it gets. So avoid aggressive cleaning with scented soaps.
Faecal contamination is another common factor leading to prutitus ani. Faeces are themselves irritant and may irritate the anal area. Several things that can lead to faecal incontinence which are as follows:
Difficulty in cleansing the area
The itch may be triggered by a bowel movement or wiping with toilet paper, but often occurs at night, waking the patient from sleep
Other diseases that have been associated with pruritus ani include the following:
Vitamin A and D deficiency
Lichen simplex chronicus,
Allergic contact dermatitis especially to perfumed soaps
Perianal streptococcal dermatitis
Squamous cell carcinoma,
Exposure to detergents
Bubble baths and urinary or faecal incontinence.
Anal warts and condyloma lata
Pruritus ani Treatment
The mainstay of treatment of anal itching is to find out the causative factor responsible for pruritus ani, once the cause has been identified, treatment can tailored accordingly. For immediate relief Sitz baths (warm water hip baths) may be beneficial.
Good toilet hygiene should be strictly followed no matter what is the cause of itching. The anal area should always be cleaned with plain water and dried with soft tissue paper when possible. Rubbing with toilet paper should be discouraged and dabbing recommended. Contact allergy to preservatives in the products are the main concern, so it is wise to avoid all perfumed products or any other products that contains preservatives, just using plain water is better option. A good moisturizer may be applied if there is dryness around the anal region.
Remember: Avoid strong/scented soaps and chemicals. No vigorous/frequent washing.
Always wear loose fitting cotton underwear. Tight fitting clothes tends to trap the moisture and also encourage sweating that can lead to more anal itching.
Stress and anxiety tends to make the itch worse so if you are going through such periods try not to scratch the itchy area. Scratching creates more damage, which in turn makes the itching worse. Always remember to trim your fingernails short so you won’t knowingly scratch during sleep. You may wear cotton gloves during sleep.
Topical ointments containing silicone or zinc may be helpful. Topical steroids are effective in case of noninfectious cause of pruritus ani especially non fungal etiology. Use of newer agents like tacrolimus is safer and effective than topical steroids. Use of topical Capsaiein 0.006% is also effective in some cases. When there is inflammation and pain, topical anti-inflammatory and anesthetic lotions (Pramoxine hydrochloride) can be applied alone or in combination with hydrocortisone.
When itching is severe at night, you may take some over the counter anti-itch medications to help reduce itching. Most individuals get relief from itchy anus within a week of initiating treatment. If the itching persist for several weeks even after treatment contact your health care provider.