Anal Abscess

An anal abscess usually develops after a small gland just inside the anus becomes infected with bacteria. This results in the formation of pus which is known as an abscess. Exactly why some people develop this type anal abscess is not certain. Anal abscesses can also occur with other conditions such as Crohn’s disease.

An anal fistula usually develops as a result of an anal abscess which is drained or bursts. Around half of people who develop an anal abscess will go onto develop an anal fistula.


Symptoms of an Anal Abscess

People suffering with an anal abscess will experience the following symptoms:

  • Pain
  • Swelling
  • Tenderness
  • Sometimes the abscess can burst on its own releasing pus.
  • Flu-like symptoms as a result of the local infection.


How is an anal abscess investigated?

When you are seen in clinic the consultant will take a full history and carry out a clinical examination.

Usually an abscess is readily apparent on examination. If the area is too uncomfortable to examine then the consultant may recommend carrying out an examination under anaesthetic to confirm the diagnosis, where the abscess can be treated at the same time.

Sometimes an MRI Scan or endoanal ultrasound scan will be recommended, particularly if the problem is longstanding or recurrent.

If you are over the age of 40 and have had any bleeding or change in bowel habit the consultant may recommend endoscopic examination of the bowel either by flexible sigmoidoscopy or colonoscopy to ensure that it is otherwise healthy, again this can often be carried out alongside treating the abscess.


Anal Abscess Treatment

An anal abscess is treated by making an incision in the skin and draining away the pus. Sometimes a drain is left afterwards to make sure that the pus doesn’t recollect. A general anaesthetic is usually required. Some patients particularly those with diabetes may require antibiotics for a few days after the procedure. Most patients will be able to go home within 24 hours of their surgery.

After the procedure patients will need to have regular dressings to the site. With smaller abscesses patients may be able to do this themselves with larger abscesses a nurse may be required to supervise the dressings.

Keeping the area clean afterwards is important particularly after bowel opening, see our advice sheet on Caring For Yourself After Anal Surgery.

Healing normally takes place over 4 to 6 weeks. Healing may not occur if an anal fistula has developed.

What are the next steps?

If you think you have this condition or any of these symptoms you will need to seek medical advice.

For more information or to make an appointment:

If you have private medical care or wish to pay to see a consultant:

Take this factsheet along to your own GP and request a referral to one of our consultants.