you could have pinworms. the live in your rectum and come out at night (don't ask me how they know it is night! ) and lay eggs around your anal ring. this is one common cause of "pruritis ani" (latin for "itchy anus"). you will need to have your medical provider order a pinworm test. if this is not the cause then you will need to see your medical provider for an exam to see if their are other treatable reasons.
why does my anus only itch at night ( 20 years old male)? . for the past week around evening time i feel extreme itching goes away after a few hours. starts again the next day at the same time