Happened to me. It is very painful. The Dr. gave me a cream to use-Diltiazem and it made it feel better and it closed it. It is a heart cream and I think it makes the blood flow to the area so it will heal better. Sitz bath help too and I would rub Rosebud Salve on the fissure to make it feel better.
I was able to move my drain so it wouldn't pull agst. the fissure too badly.