Haemorrhoids, or piles, are dilated varicose veins of the rectum or anus. They are common in middle and later life, often caused by years of chronic constipation. Usually we can differentiate three different types of haemorrhoids:
Internal haemorrhoids –slightly dilated veins which can be found inside the rectum. They are painless but often bleed. Usually treatment with suppositories or ointments is effective.
Prolapsed haemorrhoids - a more severe and painful form of internal haemorrhoids. These veins push through the anus and hang out of the body, particularly after going to the toilet. Sometimes, the anal sphincter (ring of muscle) can strangulate veins that hang out permanently.
External haemorrhoids - these are like small haemorrhages (bleeds) under the skin around the anus. They feel like hard lumps.

Blood flow is hindered
Piles develop slowly over time. Small blood vessels and veins in and around the rectum and anus carry deoxygenated blood back to the heart. If this return blood flow is hindered, then these tiny blood vessels and veins can distend with blood and eventually grow fat and knobbly. The main causes of haemorrhoids include:
Straining on the toilet because of constipation
Pregnancy, because of the extra weight and pressure on the bowels
Hereditary factors
Heavy manual labour.

Treatment

The treatment of piles depends on the severity of symptoms. The first steps should be avoiding aggravating factors such as constipation or being overweight. Both treating and preventing haemorrhoids rely on eliminating constipation. A diet rich in fibres, vegetables, fruits, cereals and water will help produce soft bowel motions that are passed easily and regularly.

You may also consider fibre.
Avoid dehydration, drink plenty supplements of water and fruit juice.
Try to keep to a regular bowel habit and go to the toilet when you feel the need to
Exercise - this helps keeps the bowels regular.
Avoid painkillers that contain codeine.

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