Passing hard stools irritates the tissues lining the anus and may
even slightly tear these tissues, causing a painful
anal fissure. Rectal pain caused by constipation can
trigger a vicious cycle. Pain discourages you from trying to have a bowel
movement, which causes constipation to worsen, which causes more pain. The pain
from passing a hard stool usually goes away within half an hour after passing
the stool.
Other causes of rectal pain include
hemorrhoids, an
anorectal abscess or
fistula,
endometriosis, and cancer of the rectum or
anus.
When rectal pain is severe or does not improve with home treatment,
a visit to a health professional is needed.