For the first few days, you have to work through the pain and constipation until you've managed to sort out your digestive tract, but I still wouldn't recommend going for constipation relief tablets which can screw up your digestion even more. I wrote up a list of advice for myself for dealing with this problem if it re-occurs, and I'm sharing it here in case it helps anyone else.
Dealing with an anal fissure
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Constipation and anal fissure damage/pain seem to go hand-in-hand, so dealing with the anal fissure and dealing with constipation and bad digestion usually go hand-in-hand.
DOs:
- Stay well hydrated (large glass of water every hour from 9:00 to 16:00; setting up reminders on a mobile phone app to drink is a good idea).
- Eat porridge *every* morning (no matter how boring this gets!)
- Have a decent amount of fibre in your diet (at least 1 apple per day, plenty of vegetables, wholegrain bread).
- Walk briskly for at least half an hour each day.
- Try to stick to about 1.5 bowel movements per day; 1-2 per day is OK, less or more is bad. This should happen automatically if your diet and exercise are good.
- Have a *hot* sitz bath for at least 5 minutes after every bowel movement.
DON'Ts:
- Don't strain during bowel movements if at all possible; always try to relax and pass stool gently. If there's enough constipation *some* straining may be necessary but with the right stool consistency, straining is never required.
- Don't take constipation relief tablets (you'll get diarrhoea which is arguably worse, and it will screw up your digestive tract's schedule).
- Don't eat any foods that are liable to lead to constipation (pizza, fried *anything*, chips, kebab, burger, white bread, cheese, etc. Yeah, lots of tasty things are off the menu. Deal with it.)
- Don't apply Anusol or other hemorrhoid treatments to the fissure; it can actually reduce blood flow to the area which will slow the healing process. For relief, use Savlon or a similar soothing antiseptic cream, although the sitz baths should usually clean the area well enough to avoid the need for this.
Stool should become soft & unsticky, and bowel movements gentle. The fissure should become less painful after a few days and heal properly over a few weeks.
Be sure to keep this regimen going for a month or so, until the fissure seems to have completely healed. At the first sign of irritation or pain, go back to this regimen *immediately* before things get worse and very painful again.
Once it's healed you can start eating the odd pizza or fried food, but it should always be a "once in a while" thing. If you eat this stuff regularly the constipation and fissure will probably come straight back.
