Anal fistula treatment

We treat an anal fistula with surgery under a general anaesthetic (a medicine that makes you sleep and stops you feeling pain). Most people can leave hospital on the same day as the surgery. 

You need a family member or friend to travel home and stay with you for at least 24 hours after your surgery. It is important that you rest for the remainder of the day.

If your fistula is complex (branches in different directions), you might need to stay in hospital overnight. 


You might have a dressing over your wound. You can remove this in a bath on the day after your surgery.

To take off the dressing, you might need to pull it gently. This can cause your wound to bleed. Do not be worried if this happens. You can contact us if you have any concerns. 

Looking after your wound

Keep the area clean and gently bathe your wound in a warm bath each day, if possible. This can also help with your pain.

Do not use soap, or put salt or any perfumed products in the water, until your wound has healed. These could irritate your wound.  

Try to wash the area or use alcohol-free wet wipes to clean your wound after doing a poo.  

Your surgeon may ask you to ‘digitate’ your wound. You move a finger along your wound to prevent the top layer of skin from healing too quickly. This might be uncomfortable, but can help to stop your fistula coming back.

If you prefer not to digitate the wound yourself or cannot reach the area, contact the practice nurse at your GP surgery. You need to ask them to do this each day.

If we put in a seton stitch, you might find that some mucus (thick, slippery fluid) leaks out of the wound. This is common. You might want to wear a pad in your underwear and bathe more often. The mucus can make the surrounding area sore and itchy. 

Your nurse explains how to care for your wound. 

Speak to the ward or department where you were treated if:

  • you keep getting bleeding from your wound 

Out of hours, contact your GP or go to your nearest emergency department (A&E). 

Ask for an urgent GP appointment or go to the nearest A&E if:

  • you feel generally unwell
  • you have a high temperature (fever) 

Pain after surgery

You can expect some discomfort after surgery. The affected area can be quite painful for the first couple of days. It might seem like the pain gets worse before you start to feel more comfortable again. 

You might have some discomfort and a little bleeding when you first do a poo. Try to go the toilet when you get the urge to do this. It can help to take painkillers about 15 to 20 minutes before you do a poo.  

When you leave the ward or after your day surgery, we might give you medicines to take home with you.


It is important that you take your prescribed amount (dose) of painkillers regularly. This helps to keep you as comfortable as possible. You might not need to take the painkillers if the affected area is pain-free.

Always follow the instructions on the packet and never take more than the recommended dose.


We might give you antibiotics to prevent infection and ease your pain.

If we give you antibiotics called metronidazole (Flagyl®), do not drink alcohol while you take the tablets. These tablets can cause unpleasant reactions if mixed with alcohol, such as:

  • feeling and being sick (nausea and vomiting)
  • flushing (sudden reddening) of the face
  • headaches
  • heart palpitations (when it feels like your heart is pounding or racing)

You can safely drink alcohol again 2 days after finishing your course of metronidazole. 

Always complete the full course of any antibiotics (take the tablets regularly, as instructed, until you have finished them all). Tell your doctor if you are allergic to any antibiotics and always ask if you have questions about any of your medicines.


We might give you laxatives to help you go to the toilet. Laxatives help you to poo and to keep your poo soft. 

Returning to work and activities

Most people take a few days off work, but this depends on how you feel and if your job is active. 

You can do as much as you feel that you can manage. However, avoid any heavy activity such as lifting, exercise or running during the first week or so.

Do not go swimming until your wound has healed. You can have sex as soon as you feel comfortable.


No routine follow up appointment is required unless specified by the surgeon.

If your condition changes, you can start (initiate) a follow-up by contacting us. This is known as patient initiated follow-up (PIFU). If you have any concerns in the initial 6 months after your surgery, you can contact us by email: [email protected]

After 6 months you should your GP to be referred back to our team.

Resource number: 0908/VER6
Last reviewed: June 2023
Next review: June 2026

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