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Anal fissures occur most commonly due to chronic constipation
. I suggest you include lots of fiber in your diet to have easy and smooth bowel movements. Drink at least 3-4 liters of water per day.
Perianal skin is sensitive and vigorous rubbing may cause contact irritation which also predisposes for infection by fungi and bacteria. I suggest you keep these areas clean and dry.
Sitz baths will help relieve pain due to fissure and also cleanse the area.