Haemorrhoids are enlarged, congested veins just under the surface tissue of your rectum (the last part of your bowel) or your anus (the opening of your bowel).
Haemorrhoids that occur in your rectum are called internal haemorrhoids, and those that occur around your anus are called external haemorrhoids.
Haemorrhoids are common — about 50 per cent of adults have had them by the time they turn 50 — and are also called ‘piles’.
Haemorrhoids can become swollen, painful and inflamed (‘flare up’) and bleed when irritated. You may notice blood (usually bright red) on the toilet paper or in the toilet after having a bowel movement, and bleeding can be painless.
They may be itchy or associated with a mucous discharge.
At other times, when they are not swollen or irritated, they may cause no symptoms.
Internal haemorrhoids come from veins inside the rectum and usually can’t be seen from the outside. However, they can bleed, especially when you pass a stool. You might notice streaks of bright blood on the outside of a stool or on the toilet paper when you wipe your bottom, or splashes of blood in the toilet bowl.
Internal haemorrhoids can cause mucus to leak from the rectum onto the anal skin. This moisture encourages secondary skin infections, and results in the itchiness that often accompanies haemorrhoids.
Internal haemorrhoids are not usually painful, but if one becomes very large, it can hang out of the anus (called a ‘prolapsed haemorrhoid’), causing pain and increased swelling.
External haemorrhoids come from veins outside the anus. They look like one or more firm grape-like swellings on the outside of the anus. External haemorrhoids can become painful and irritated, and can bleed or itch. Blood pooling in an external haemorrhoid can lead to a blood clot forming in the haemorrhoid. This results in a firm, bluish swelling on the edge of the anus that is very painful. This pain usually intensifies over about 3 days then settles as the clot resolves.
Some people have both internal and external haemorrhoids.
When a swollen haemorrhoid subsides, the area of anal skin that overlies it can hang a bit loose, because it was stretched when the haemorrhoid was swollen. This small area of loose skin is called a ‘skin tag’. Several skin tags can give the anus a ruffled rather than a smooth appearance. Skin tags do not usually cause discomfort but they can make cleaning your bottom after passing a motion more difficult. It is best to wash the area or use a moist disposable wipe, rather than dry toilet paper.
What causes haemorrhoids?
Doctors do not always understand exactly what causes haemorrhoids, but increased pressure in the veins of the rectum and anus and downwards sliding of the tissue containing these veins are thought to be involved. The increased pressure may be caused by:
Some people seem to inherit a tendency to develop haemorrhoids — this may be due to weakness of the tissues supporting the veins in the anus and rectum. This weakening can also occur with increasing age.
Constipation, failure to pass a stool when needed, eating a diet that is low in fibre, not exercising regularly, and not drinking enough fluids can lead to constipation, which increases your likelihood of developing haemorrhoids.
Tests and diagnosis
Your doctor will ask about your symptoms and perform a physical examination. It’s important that anyone experiencing rectal bleeding sees their doctor so that the cause can be determined – don’t assume that haemorrhoids are the cause.
To exclude other possible causes of bleeding, your doctor may recommend further examination of the bowel via sigmoidoscopy or colonoscopy. During these tests, a thin, flexible tube with a camera on the end is used to examine the inside of the bowel. Tissue samples (biopsies) can be taken during these tests if necessary.