A seton is a thread, loop, or rubber band placed through the fistula tract — from the internal opening inside the rectum, through the tract, and out through the external opening on the skin. It keeps the tract open and draining, prevents abscess formation, and allows the area to heal gradually. Different types of setons serve different purposes — some are purely for drainage, while others slowly cut through tissue.

Is seton placement painful?

The procedure is performed under anaesthesia, so you will not feel pain during placement. Post-procedure discomfort varies — most people describe tenderness and soreness for the first few days that is manageable with prescribed or over-the-counter pain relief. The first bowel movement after placement is commonly described as the most uncomfortable moment.

How long does a seton stay in?

The duration varies widely depending on the type of seton and the treatment plan. Draining setons may stay in for weeks to months. Cutting setons are designed to gradually work through tissue over a longer period. Your surgeon will discuss the expected timeline for your specific situation.

Can I exercise with a seton?

Many people resume gentle exercise within a few weeks of seton placement. Walking is usually the first activity to return. More vigorous exercise — particularly activities involving the lower body or sitting — may take longer to become comfortable. Your surgeon can advise on what is appropriate and when.

Will I have discharge with a seton?

Yes. Discharge is normal and expected — the seton is specifically designed to keep the fistula tract open and draining. Managing this discharge with pads, good hygiene, and regular cleaning is part of daily life with a seton.

Seton placement: what to expect

At a glance

Having a seton placed for an anal fistula is a common procedure. A seton is a thread or loop that is placed through the fistula tract to keep it open, allow drainage, and prevent abscess formation. The procedure is relatively brief and usually performed as a day case.

This guide covers what happens before, during, and after seton placement so you know what to expect.

Before the procedure

Pre-operative preparation

Pre-operative assessment — blood tests, medical history
Fasting instructions — typically from midnight the night before
Bowel preparation if advised by your surgeon
Arranging transport home

What to bring

Loose, comfortable clothing
Absorbent pads — you will need these from the start
Someone to drive you home

The procedure

Anaesthesia

Seton placement is typically performed under general anaesthetic, though regional or local anaesthesia with sedation may be used. The anaesthetist will discuss options with you.

What happens

Examination under anaesthesia (EUA): The surgeon examines the fistula tract thoroughly — often using a probe to map its course
Abscess drainage: If there is an abscess present, it is drained at the same time
Seton threading: The seton is passed through the fistula tract — entering through one opening and exiting through the other
Securing: The seton is tied loosely or secured so it stays in place

The procedure typically takes 20 to 40 minutes, depending on the complexity of the fistula.

Types of setons

Draining (loose) seton: A soft loop that keeps the tract open for drainage. It is not designed to cut through tissue and sits loosely.
Cutting seton: A tighter loop that gradually cuts through the tissue it encircles. This is tightened over time at follow-up appointments.

Your surgeon will explain which type is being used and why.

After the procedure

In the recovery area

You wake from anaesthetic or the sedation wears off
Pain medication is provided
You rest until cleared to go home

The first 24 to 48 hours

Pain: Soreness and tenderness around the seton site — manageable with prescribed pain relief
Discharge: Blood-tinged fluid is normal — have pads ready
Rest: Take it easy, avoid strenuous activity
Sitz baths: Most surgeons recommend starting sitz baths the same day or the next day

The first bowel movement

This is a common anxiety point. People describe:

Dreading it more than the procedure itself
Finding it either surprisingly manageable or uncomfortable but brief
Sitz baths afterwards providing significant relief
The importance of keeping stools soft with stool softeners started before the procedure

The first week

Pain typically settles significantly within five to seven days
Discharge continues — this is expected and part of the seton’s function
Sitz baths two to three times daily
Short walks increasing gradually
Follow-up appointment usually within one to two weeks

Living with a seton

The adjustment to life with a seton takes time. Key aspects:

Hygiene: Keeping the area clean is a daily priority — see our seton hygiene guide
Discharge management: Pads and regular changes — this becomes routine
Pain: Varies from barely noticeable to moderate, depending on the day — see our seton pain guide
Activity: Most daily activities resume within one to two weeks
Follow-up: Regular appointments to assess the fistula and, for cutting setons, to tighten the seton

When to contact your surgical team

Seek medical attention if you experience:

Increasing pain, swelling, or redness near the seton
Fever or chills
Discharge that becomes foul-smelling or changes significantly
The seton appearing to have moved or fallen out
Any symptoms that concern you