A fissure is a painful crack in the anus, usually caused by constipation and the passage of hard motions. It can be extremely painful & slow & reluctant to heal.

To help it heal:

• Take a high residue diet. The best way to do this is to eat Natural Bran, which can be obtained from Boots Chemists, Health Food shops & some other food stores, such as Safeway's & Sainsburys. Take 3 tablespoonfuls (i.e. 3 large spoonfuls) every day. Natural Bran is very dry & should be taken mixed with or sprinkled over moist food or fluids. For example sprinkle 3 tablespoonfuls of Natural Bran over your cornflakes and milk or porridge during breakfast. You should drink plenty of fluids when taking Natural Bran. To supplement your high residue diet, eat wholemeal bread, (e.g. Allinson’s Stoneground) instead of white bread. If despite this you remain constipated in addition take the medication Lactulose (which can be obtained without a prescription) up to 10mls (2 teaspoonfuls) 3 times a day.
  

• Apply the gel provided (e.g. Xylocaine or Lignocaine gel) to your anus, with a gloved fingertip 10 minutes prior to a bowel action. This may initially sting but will then anaesthetise (make numb) the area to reduce or stop the discomfort when motions are passed.
  

• Keep your anal area clean & dry. If possible bathe the area once or twice daily, e.g. after a bowel action or before retiring to bed, in lukewarm water to which half a teacupful of Savlon has been added. Dry thoroughly by gently wiping the area &, if possible, by the use of a hairdryer on the cool setting. Only after it has been dried thoroughly, you may, if you wish, dust the area with a small amount of Johnson’s baby powder.