Itchy Rectum and Anus – Introduction

Anal canal is the last, 2-4 cm long part of the large intestine that ends with the anal opening (anus). Rectum is about 12 cm long part of large intestine between sygmoid colon and anal canal.

Picture of Rectum and Anal Canal

Rectum lesions actually doesn’t itch (but may be painful), since there are no itch receptors (special nerve endings) in rectal mucosa. However, changes may extend from rectum to anal mucosa or groin skin, and these may itch.

Poor Hygiene

Dried feces, dust, scaled skin cells, and sweat, one by one, or all together may cause itchy skin around the anus. Washing with warm or lukewarm water without soap is recommended. Moistened tissues may be used when anus is sensitive.

Dry Skin

Dry skin may cause anal itch, especially in old people and in those who frequently use hot showers or baths. Solution is in avoiding hot showers, and using moisturizing creams like glycerine (but not petroleum jelly like Vaseline).

Spicy Food

Certain foods such as hot spices, caffeine, beer, wine, carbonated beverages, prunes, figs, milk products, nuts, pop-corn, chocolate, tomatoes and citrus fruits cause anal itch, they should be avoided. In some cases irritation is caused by food allergy.

Seborrheic Dermatitis

Seborrheic dermatitis is skin inflammation due to excessive excretion of oil by sebaceus (oil) glands and subsequent infection with Malassezia yeasts. Itchy, scaly yellowish patches of skin appear in groin, armpits, around the nose or ears, and on the scalp. Treatment includes ointments and shampoos containing selenium sulfide, pyrithione zinc, ketoconazole, terbinafine, sodium sulfacetamide, and corticosteroids.

Scratching

Scratching is one of main reasons for itchy anus. Scratching aggravates existing itch, so – do not scratch.

Hemorrhoids

Hemorrhoids are varicose veins in anal region. They are located either inside the anus (internal hemorrhoids) or under the skin around the anus (internal hemorrhoids).

Internal hemorrhoids usually can’t be felt, but they may bleed. If they become big, they may protrude out from the anus. If hemorrhoidal veins get thrombosed (clotted), itching and sometimes severe pain may appear.

External hemorrhoids appear as bluish, tender, soft lump, bulging out from anal circumference. They may itch or burn, especially after prolonged sitting, or straining.

Hemorrhoids may develop in obesity, repeated prolonged sitting, constipation, repeated straining at bowel movements, and in pregnancy. Lack of dietary fibers and fluid, lack of activity (physical and/or psychical), and several medications also contribute to constipation. Further reading about chronic constipation .

Mild to moderate hemorrhoids resolve by their own in few days. Over-the-counter hemorrhoidal cream can be obtained in pharmacies. Chronic, non-resolving hemorrhoids can be treated with different non-surgical (rubber banding, arterial ligation, freezing) or surgical methods.

Diarrhea and Bowel Incontinence

Diarrhea or bowel incontinence with frequent flow of bowel contents over anal mucosa, and frequent wiping may cause anal itch. The cause has to be removed (food poisoning, intestinal parasites, etc).

Fungal Infection

Fungal infection with Candida albicans (picture) tends to appear in moist skin areas, like in the groin. Long term antibiotics, steroids, chemotherapy, and disorders with low immunity promote candida growth. Tinea cruris causes jock itch, mostly in people who constantly have moist groin, typically in athletes.

Fungal infection appears as red or brown, scaly, itchy rash that may affect extensive areas of inner thighs, groin, and buttocks.

Treatment is with over-the-counter antifungal ointments, or in severe cases with prescribed medications by mouth. Low sugar diet is recommended.

Bacterial Infection

In perianal streptococal dermatitis, bright red, itchy rash appears in the groin area, in children between 6 months and 10 years of age. Blood streaks may appear on the stool. The cause is infection with group A beta-hemolytic streptococci. Treatment with antibiotics is effective, but re-occurrence is common.

Erythrasma is a rash, appearing in skin folds (armpits, groin), caused by Corynebacteria minutissimum. It mostly affects people in hot climates, and those with diabetes. Rash may itch, but usually there’s no symptoms. Treatment is with antibacterial ointments.

Intestinal Parasites

Pinworm (Threadworm)

Pinworms are intestinal parasites, often living in colon or rectum in children worldwide. They are 1-2 cm long and they may leave the rectum at night and deposit eggs on surrounding skin, and cause anal itch. Diagnosis is with the stool test for ova and parasites (O&P).Treatment is with prescribed, or over-the-counter anti-parasite medications.

Blastocysis Hominis

Blastocystis hominis is microscopic parasite, that may cause diarrhea, nausea, fatigue and anal itching, but is often present without any symptoms.

STDs

Common symptoms of sexual transmitted diseases (STDs) are burning at urination, uretheral discharge or bleeding, and sometimes fever. The following STDs may also cause anal itch:

Chlamidia trachomatis may cause rectal pain, discharge, or bleeding 1-3 weeks after anal intercourse. Burning at urination and discharge from urethra may appear. Low back pain and bleeding between periods may appear in women. Treatment is with antibiotics. Chlamidia may affect reproductive organs and cause infertility in women.

Gonorrhea is infection caused by bacterium Neisseria gonorrhoeae. Anal, vaginal, or urethral discharge, bleeding, pain and itchiness may appear 2-5 days (or even 30 days) after infection. Treatment is with antibiotics.

Genital herpes caused by Herpes simplex virus (HSV-1 or HSV-2) may be extremely painful and itchy. Small translucent blisters appear on reddened skin around anus (or on mucosa of vulva or penis) within 2 weeks after infection, they may persist for 2-4 weeks, and leave tender ulcers. A person infected with HSV for the first time may expect reactivation of virus for 4-5 times within the year. Treatment of severe cases is with antiviral pills.

Anal warts (condyloma) are small flat growths of skin around the anus, appearing weeks or months after sexual contact. These are actually genital warts, appearing on or around genitals and anus. They are caused by Human papilloma virus (HPV), and transmitted by direct skin to skin contact. They may itch or bleed, and may go off, or increase in size with time. They don’t develop into cancer. They can be frozen or surgically removed. Picture of anal warts (Condyloma acuminatum).

Moluscum contagiosum is another type of warts, caused by a virus that may be transmitted by sexual contact. They appear as small, red or brown, waxy, dome-shaped, umbilicated bumps. They can be removed by various “small-surgery” methods like freezing, electrocautering, etc.

In children, molluscum contagiosum may appear anywhere on the skin. It is spread by skin-to-skin contact. Warts disappear within a year.

Pubic lice (crabs) cause itch in the groin area. Eggs or adult lice may be found. Transmission is via sexual contact. Treatment is with over-the-counter lice-killing lotions.

Pubic lice - Pediculosis pubis

Picture 2. Pediculosis pubis
(source: Samuel Freire da Silva, M.D., atlasdermatologico)

Syphilis is caused by bacterium Treponema pallidum, and transmitted by contact with a sore (chankre) that may appear on genital mucosa, anus, lips or in the mouth. A small, red, firm, painless sore(s) appears at the site of bacterial entry 10-90 days after infection, persists for 3-6 weeks, and then heals on its own. If there is no treatment, in following weeks, non-itchy red rash may appear on the skin.

Syphilis in the early stage can be easily cured with antibiotic penicillin.

Eczema

Eczema in the groin appear as itchy, reddened flaky area, and may be due to irritation by diapers, new unwashed underwear, constant irritation by clothes, soap, allergies, etc. Prevention is by avoiding irritant substances, and keeping groin area dry (wearing comfortable and airy cotton underwear and pants) and clean.

Treatment is with ointments prescribed by the doctor.

Inverse Psoriasis

Inverse psoriasis occurs in skin folds, including the groin, armpits, and skin under breasts. It appears as smooth, red, itchy, non-scaly patches. Psoriasis is genetic disease, it is not contagious, and treating of the cause is not known to the date. Treatment of symptoms is with topical moisturizing creams and immunosuppressants like Protopic and Elidel.

Anal Skin Tags

Anal tags are small soft fleshy bumps of the mucosa, hanging from anus like drops. They are common, and beside itch they rarely cause any problems. They result from chronic irritation or inflammation of anal mucosa. They can be surgically removed.

Hidradenitis Suppurativa

Hidradenitis suppurativa is inflammation and infection of hair follicles, oil and sweat glands. Itchy, painful lumps that may break and drain fluid bulge out from the skin between buttocks. They also often appear in inner thighs, armpits, or on the nape of the neck, and they may leave scars. Treatment is with corticosteroids, antibiotics, and surgery.

Crohn’s Disease and Ulcerative Colitis

Crohn’s disease and ulcerative colitis are inflammatory bowel diseases of uncertain cause, mostly affecting young adults between 20-30 years of age. Ulcers and fissures affecting anal mucosa may be itchy or painful and may bleed. Diarrhea, nausea, abdominal pains, fatigue, and low grade fever can appear. Treating is with anti-inflammatory drugs like sulfasalazine, or with surgery, if necessary.

Anal Fissure, Abscess and Fistula

Anal fissure is painful, linear crack of anal mucosa and skin near the anus that may result from straining at defecation, injury, or inflammation like Crohn’s disease. Treatment is with avoiding straining, appropriate diet that gives soft stools, corticosteroid creams or suppositories, nitroglycerin ointments, analgesics, or, if fissure doesn’t close on its own in several weeks, with surgery.

Peri-anal abscess is accumulation of pus in the anal wall or in the tissues that surround anus. It is usually a result of chronic bowel inflammation or infection with parasites, inflammation of prostate, or rarely a complication of surgery. Sometimes peri-anal abscess may be seen as a bulge (few cm in size) from the skin near the anus, or may be felt during rectal examination. Treatment is with antibiotics by mouth or surgical drainage.

Anal fistula is a tinny tunnel that starts in anal or rectal mucosa, flows through tissues that surround anal canal, and opens in the skin beside anus. It may itch, and bowel contents may exit through it. Surgical excision is usually needed.

Details about anal fissure, abscess and fistula

Anal Carcinoma

Anal carcinoma may be painful, itchy, and may bleed. It rarely occurs before 50 years of age. Treatment is surgical removal. Non-cancerous polyps may be removed during rectoscopy (or colonoscopy).

Common Anorectal Conditions – Pictures and Treatment

Prevention of Anal Itch

General measures to prevent anal itch:

  • Gentle but thorough wiping after bowel movements is essential. Moistened tissues may be used.
  • Wash anal region with lukewarm water, and without soap.
  • Never scratch the anus.
  • Avoid all perfumes, deodorants and medical powders.

Treatment of Anal Itch

The following can be done:

  • Find and treat the underlying cause if possible.
  • Topical moisturizing creams can help to soothe affected area. Only weak topical steroids (1% hydrocortisone cream) should be used to avoid thinning of sensible skin around the anus, but only for few days, never for long periods.
  • Suppositories and home remedies should be avoided.
  • Avoid constipation and straining.

Further Reading:

Types of Skin Rashes
Itchy Skin – Prevention and Treatment
Itchy Skin – Causes
Itchy Armpits
Itchy Legs


Article reviewed by Dr. Greg. Last updated on August 3, 2013