Other problems that can contribute to anal itching include pinworms, hemorrhoids, tears of the anal skin near the mucocutaneous junction (fissures), and skin tags (abnormal local growth of anal skin). Aside from diseases relative to the condition, a common view suggests that the initial cause of the itch may have passed, and that the illness is in fact prolonged by what is known as an itch-scratch-itch cycle. It states that scratching the itch encourages the release of inflammatory chemicals, which worsen redness, intensifies itchiness and increases the area covered by dry skin, thereby causing a snowball effect. Some authorities describe “psychogenic pruritus” or "functional itch disorder", where psychological factors may contribute to awareness of itching. Ingestion of pinworm eggs leads to enterobiasis, indicative of severe itching around the anus from migration of gravid females from the bowel. Severe cases of enterobiasis result in hemorrhage and eczema. Diagnosis
Diagnosis is usually done with a careful examination of the anus and the patients history. If the presentation or physical findings are atypical, biopsies can be done.In case of long-lasting symptoms, above all in patients over 50 years of age, a colonoscopy is useful to rule out a colonic polyp or tumor, that can show pruritus ani as first symptom. Treatment
The goal of treatment is asymptomatic, intact, dry, clean perianal skin with reversal of morphological changes. For pruritus ani of unknown cause (idiopathic pruritus ani) treatment typically begins with measures to reduce irritation and trauma to the perianal area. Stool softeners can help prevent constipation.
After this, they must maintain their clean and dry regime and apply an emollient ointment (not cream) to moisturize the skin. This should be applied after each bowel movement and at night. Continue until no longer needed. At any time, persons may use antihistamine treatments orally, to control the itching. See also
Pruritus scroti
Pruritus vulvae
Perianal candidiasis

References
External links
Siddiqi S, Vijay V, Ward M, Mahendran R, Warren S (September 2008). "Pruritus ani". Annals of the Royal College of Surgeons of England. 90 (6): 457–463. doi:10.1308/003588408X317940. PMC 2647235. PMID 18765023.