A sudden contraction of severe pain in the anus is considered to be the following: a. It may be due to the nucleus of the hemorrhoid protruding outside the anus or stuck in the anus causing impaction, which manifests as persistent pain, along with edema of the nucleus, congestion and blood in the stool. Second, it may be caused by anal fissures. Anal fissures are painful periodically, mainly when the wound is irritated by fecal urine during stool, and there is a strong tearing sensation, which later causes pain similar to fire or like a knife cut. Third, it may be spasmodic anorectal pain, the pain comes suddenly, lasts for a relatively short time and can recover on its own, other diseases of the anus such as anal fistula and anal inflammation may also appear this symptom. It is best to go to the anorectal department of the hospital for further examination to determine what is causing the condition and to treat it under the guidance of the doctor.