Anal Surgery

Drainage of perianal abscess

If you have a perianal abscess, you are probably in a lot of pain right now — and that is completely understandable. Draining the abscess promptly is the most important step: it brings quick relief, stops the infection spreading, and allows the area to start healing.

CSSANZ RACS Austin Health Warringal Private Hospital Epworth ANZ Hernia Society CCRTGE BCOR
Overview

A perianal abscess is a pocket of pus that forms when one of the small glands near your anus becomes infected. The pressure this creates is what makes it so painful. In most cases it needs to be drained surgically — under a general anaesthetic so you feel nothing during the procedure. The abscess is carefully opened to release the pus, a sample of the fluid is sent to the lab so the right antibiotics can be chosen if needed, and the area is examined for a fistula — a small tunnel connecting the gland to the skin — that might need treatment later. In published series, around 30–40% of perianal abscesses turn out to have a fistula already present at the time of drainage, which is why a thorough look while you are under anaesthetic matters so much.

Who needs this procedure?
  • You have a perianal abscess — a painful, swollen lump near your anus that may be causing fever or making you feel generally unwell
  • You have an ischiorectal abscess — a deeper collection of infection sitting in the fat beside the bowel that needs draining under anaesthetic
  • You have a supralevator abscess — a more complex, higher-up abscess that requires careful planning to drain safely
  • Antibiotics alone have not settled the infection — most abscesses need physical drainage, not just medication
  • You have had a perianal abscess before, which may suggest there is an underlying fistula that keeps causing it
  • Your immune system is weakened (for example due to diabetes, Crohn's disease, or medications), meaning the infection needs urgent attention before it spreads
Benefits
  • Most people feel substantial pain relief soon after the abscess is drained — often within hours
  • Draining the abscess stops the infection spreading deeper into the surrounding tissues, which avoids more serious complications
  • Examination under anaesthetic allows a thorough check for a fistula while you are already asleep — no extra procedure needed
  • The pus is sent to the lab so the team knows exactly which bacteria caused the infection and which antibiotic would work best if one is needed
  • For most straightforward abscesses this is a day procedure — you go home the same day
  • Getting it drained promptly gives you the best chance of avoiding a long-term fistula
Risks & considerations
  • Fistula development — in published series, around 30–50% of people develop a clinically-evident anal fistula (a small tunnel between the gland and skin) in the months that follow abscess drainage. This sounds alarming, but fistulas are treatable and you will be monitored closely. Many people never develop one
  • Slow wound healing — the wound is left open on purpose to allow it to drain and heal from the inside out. This takes 3–8 weeks and can feel frustrating, but it is normal and important for preventing recurrence
  • Recurrence — if there is an underlying fistula that was not detected at the time, the abscess can come back. This is exactly why the area is examined carefully while you are under anaesthetic
  • Incontinence (loss of bowel control) — this is rare for straightforward perianal abscesses. The risk is somewhat higher for deeper or more complex abscesses (such as ischiorectal or supralevator ones, listed above) where more extensive drainage may be needed. The drainage is planned to spare the sphincter muscles wherever possible
  • Wound infection or spreading redness (cellulitis) — uncommon, and easily treated with antibiotics if it occurs
  • Bleeding — usually minor and controlled with a dressing or packing placed in the wound
Before the procedure

If you take blood thinners, diabetes medication, GLP-1 weight-loss injectables, or iron supplements, please flag this when you book — these need specific adjustments before the procedure. Full details are in the guide above.

  • This is treated as semi-urgent — the practice team will aim to get you to theatre within 24–48 hours of seeing you, because the sooner it is drained the better you will feel
  • If you have a fever or feel generally unwell, you may be started on antibiotics before your procedure to calm the infection slightly
  • You do not need to do any bowel preparation (no laxatives or enemas) for a standard abscess drainage
  • Before your procedure, the planned operation is explained, any questions are answered, and you will sign a consent form. The possibility of a fistula being found, and what that would mean for any further treatment, will also be discussed
On the day
  • You will be admitted to Warringal Private Hospital or Epworth Eastern, usually as a day-case or short overnight stay, and given a general anaesthetic — you will be completely asleep and comfortable throughout
  • The abscess is opened — either with a small incision or by removing the overlying skin — and the infected material inside is gently cleaned out
  • The wound is flushed clean, then loosely packed with a soft dressing to help it drain and heal
  • A fine probe is carefully used to check whether there is a fistula tract (a tunnel) connected to the abscess
  • A swab of the pus is sent to the microbiology lab to identify the bacteria involved
  • You will wake up in recovery, then move to the day-stay unit. Once the nursing team is happy you are comfortable and able to manage at home, you will be discharged with clear wound care instructions and pain relief medication
Recovery & aftercare
  • Days 0–2: The area will still be sore — this is normal after an abscess that was so painful to begin with. Take your pain relief regularly (do not wait until the pain is bad to take it), and start warm sitz baths — sitting in a shallow bath of warm water for 10–15 minutes, two or three times a day. This soothes the wound and helps it drain
  • Days 3–7: Most people notice a real improvement in pain by this point. You will need to keep the wound clean and lightly dressed — a district nurse can visit you at home to do this, or the practice team will show you how to manage it yourself
  • Weeks 2–8: The wound heals gradually from the inside out, which takes time. Eating plenty of fibre and staying well hydrated helps keep your bowel motions soft and comfortable while things settle
  • If a fistula develops: If you notice the wound is not healing or a new track appears on the skin, this likely means a fistula has formed. Do not be alarmed — this is manageable. Options include a seton insertion (a small thread placed through the fistula to treat it gradually) or a fistulotomy (opening the fistula to allow healing); which option suits your situation will be discussed at follow-up
  • Contact the rooms promptly if you develop increasing pain, a fever, or notice new swelling or redness — these things are worth getting checked
  • A follow-up appointment is routinely arranged 2–6 weeks after your procedure to check how your wound is healing and plan any further treatment if needed — this review is provided at no charge
  • For day-by-day instructions on sitz baths, wound dressings, pain control, and what to watch for, see the Post-anal-procedure aftercare guide on the Resources page.

Post-operative concerns: Please call our rooms on (03) 9816 3951 and leave a message — this will be sent directly as a text to Mr Nguyen. Alternatively, you may text the office mobile on 0499 090 126. We aim to respond promptly during business hours.

Emergencies: For any life-threatening emergency, call 000 immediately or go to your nearest emergency department. Do not wait for a call back from our rooms. For the Austin Hospital Emergency Department: (03) 9496 5000.

Questions about your drainage of perianal abscess?

Mr Nguyen sees patients in Heidelberg and operates at Warringal Private and Epworth Eastern. A GP or specialist referral is required.

General information only — not medical advice. Always consult a qualified healthcare practitioner. Last reviewed · May 2026
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