Causes of constant itching in anus, also called as Prutritis Ani medically. There are multiple causes, that I will discuss which will be simpler and easy to understand. If there is any skin disease which can cause itching anywhere in the body, similar thing is there in the perianal region, patient can have itching, for example if the patient has got eczema of perianal region, he can have lot of itching. The other common cause is infections, especially fungal infections in the anal region. That causes itching, the there is worm infestation, threadworm can lay lot of eggs, that can cause a lot of itching. So that is one more cause. Sometimes small secretions or leaking can cause discharge or a little pus coming out form and that can also irritate and cause itching. Post operatively when there are wounds in that area and they are healing that times also they will have itching. The other cause is psychosomatic , where psychological causes also causes a lot of itching. That is one of the most difficult to treat because there are no psychical causes but psychological cause. This is the most common cause of itching.
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