Skin irritation:
Friction and moisture can irritate the sensitive skin in the anal area. This irritation sometimes causes anal itching. Scents, dyes and softening agents in products such as soap and toilet paper may also trigger irritation and anal itching. Overuse of these products often aggravates the problem.

Digestive problems:
Repeated bouts of diarrhea can cause anal irritation and itching. Accidental leakage of feces (fecal soiling or incontinence) is often a contributing factor.

Hemorrhoids:
Hemorrhoids are engorged veins located just under the membrane that lines the lowest part of your rectum and anus. They often occur as a result of straining during a bowel movement. Anal itching can be a symptom of hemorrhoids.

Infections:
Sexually transmitted infections may also involve the anus and can cause anal itching. In children, the parasite that causes pinworms can cause persistent anal itching. Adults in the same household can also be infected. Other parasites may cause similar itching. Yeast infections, which usually affect women, can also cause itching in the anal area.

Skin disease:
Sometimes, anal itching is the result of a specific skin disease, such as psoriasis or contact dermatitis.

Anal tumors:
Rarely, benign or cancerous tumors in or around the anus may be a cause of anal itching.