Haemorrhoids are cushions of tissue containing blood vessels in the lower portion of the rectum or anus. They are normal; everyone has haemorrhoids. They help with bowel control, especially of gas. If they become enlarged or swollen they can cause symptoms.

Causes and risk factors

Enlarged haemorrhoids are very common, especially during pregnancy and after childbirth. They result from increased pressure in the veins of the anus. This pressure causes the veins to swell. Another common cause is excessive straining during bowel movements.

Causes of haemorrhoids include:

  • Excessive straining during bowel movements
  • Constipation
  • Pregnancy
  • Rarely, diseases including pelvic tumours and liver cirrhosis

Types of haemorrhoids

Haemorrhoids may be inside or outside the body. Internal haemorrhoids occur just inside the anus, while external haemorrhoids occur at the anal opening. In general, symptoms are caused by internal haemorrhoids.

Common symptoms of haemorrhoids include anal itching, ache (especially while sitting), and bright red blood on the toilet tissue, on the stool, or in the toilet bowl.

Internal haemorrhoids may prolapse (“come down”) during straining. They usually return inside once straining stops.

External haemorrhoids can be felt as bulges, or excess skin, at the anus, but usually they cause few of the symptoms of internal haemorrhoids.

Haemorrhoids rarely cause pain, unless they become trapped outside the anus. This is referred to as a thrombosed haemorrhoid. Thrombosis of a haemorrhoid causes an anal lump that is very painful and often requires medical attention. If pain is a significant symptom, another diagnosis (such as anal fissure) should be considered.

Occasionally, external haemorrhoids can form large skin tags, which can make anal hygiene difficult or irritate the surrounding skin.


The true importance of investigating haemorrhoids is to exclude other causes of passing blood, such as colon or rectal cancer, polyps, and colitis. Before deciding on treatment for haemorrhoids, it is important to examine the bowel, either by flexible sigmoidoscopy or colonoscopy.


As it is believed that haemorrhoidal symptoms are exacerbated by straining, it is recommended that individuals soften their stools by increasing fibre in their diets. Fibre is found in numerous foodstuffs including fresh and dried fruits, vegetables, grains, and cereals. Generally 20-30 grams per day of fibre are recommended. Fibre may also be consumed in liquid form, found in a number of over-the-counter preparations.

A variety of topical treatments and ointments are available. While they may reduce some of the symptoms, they do not have any effect upon the haemorrhoids themselves. Symptoms are likely to recur. There is little scientific evidence that they provide benefit.

There is a number of non-operative treatments for internal haemorrhoids, of which rubber band ligation (“banding”) is the most commonly performed. This causes inflammation in the haemorrhoid, producing scarring over a number of weeks. The scarring causes the haemorrhoids to shrink, preventing them being traumatised and bleeding when straining. Injection of haemorrhoids with a scarring agent is a related therapy. These treatments do not require a general anaesthetic as they do not cause pain.

Surgery for haemorrhoids

The vast majority of patients with haemorrhoids are managed with non-surgical techniques. It is estimated that less than 10% of patients with haemorrhoids require surgery.

Some patients require a formal haemorrhoidectomy, where the internal and external haemorrhoids are surgically removed. The wounds may be sutured (stitched) together (closed technique) or left open (open technique). The results with both techniques are similar.

A stapled haemorrhoidopexy may also be performed, to remove the lax tissue around the haemorrhoids. This will prevent haemorrhoids prolapsing, but has no effect upon external haemorrhoids. While post-operative pain is less than with a formal haemorrhoidectomy, there is a risk of significant bleeding.

Pain is a major problem following haemorrhoidectomy, often requiring powerful pain medication. Patients usually do not return to work for 2 weeks following surgical haemorrhoidectomy.