This page provides information about what to expect when having an injection for piles.

What are haemorrhoids (piles)?

Haemorrhoids are swollen blood vessels around the anus. This happens when the pressure in the vessels is increased over long periods, for example during pregnancy or due to prolonged difficulty emptying your bowels causing excessive straining.

How does injection treatment work?

Injection treatment involves the surgeon passing a short tube into the back passage in order to see the piles. A needle can be passed into the anus via the tube to inject an oily sclerosant solution (oily phenol). The sclerosant works by causing scarring within the blood vessels, cutting off the blood flow to the piles and causing them to shrink.

What to expect after the treatment

Immediately after the injection you may feel mild discomfort in the back passage and have some bleeding from the piles. This is normal so please do not worry.

You may feel a little light-headed shortly after the procedure. It is usually best to sit quietly for 20 to 30 minutes before driving or using public transport in case you feel faint.

Over the next 2 days or so, the inflammation in the piles will settle down but you might have some irritation or discomfort, especially when going to the toilet. Mild pain relief such as paracetamol will help with any discomfort.

As the piles shrink there may be a little bleeding, but after 4 or 5 days the treatment should have worked.

Possible complications of the treatment

Occasionally the injection causes an infection or abscess where the haemorrhoids used to be.

If you experience severe persisting pain in the back passage, fevers or heavy discharge from the anus, please contact your GP for advice.

How to prevent the piles recurring

A good bowel habit is the key to stopping piles from forming. This can be achieved by following the advice below:

  • Prevent motions (stools) from becoming too hard by eating a diet high in fibre, drinking plenty of fluid (aim for a total of 2 litres of water or squash per day – tea and coffee does not count) and, if necessary, by using mild laxatives such as Lactulose® or Fybogel®.
  • Try not to strain when passing motions. Go to the toilet when you feel the need and do not try too hard to push.
  • Do not spend too long on the toilet; about 5 minutes is enough. If you sit down too long it can cause the lining of the back passage to swell.

Printable version of this page

Injection treatment for piles GHPI0881 Department: Colorectal Review due: December 2023 PDF, 502.0 KB, 2 pages
Reference number GHPI0881_12_20
Department Colorectal
Review due December 2023