This site is intended for healthcare professionals

Go to /sign-in page

You can view 5 more pages before signing in


Last reviewed dd mmm yyyy. Last edited dd mmm yyyy

Authoring team

The causes of haemorrhoids are not well understood but the following factors are important:

constipation and prolonged straining at stool - this puts downward pressure on the anal vascular cushions and causes engorgement and dilation of haemorrhoidal tissue

  • the typical Western diet is low in fibre and haemorrhoids are more common
  • haemorrhoids are uncommon in developing countries

  • increased anal sphincter tone:
    • several effective treatments aim to reduce anal tone, including anal stretch procedures and nitroglycerine ointment

  • obstruction of venous flow may play a role:
    • during pregnancy
    • in patients with portal hypertension

Related pages

Create an account to add page annotations

Annotations allow you to add information to this page that would be handy to have on hand during a consultation. E.g. a website or number. This information will always show when you visit this page.

The content herein is provided for informational purposes and does not replace the need to apply professional clinical judgement when diagnosing or treating any medical condition. A licensed medical practitioner should be consulted for diagnosis and treatment of any and all medical conditions.


Copyright 2024 Oxbridge Solutions Limited, a subsidiary of OmniaMed Communications Limited. All rights reserved. Any distribution or duplication of the information contained herein is strictly prohibited. Oxbridge Solutions receives funding from advertising but maintains editorial independence.