Haemorrhoids are like varicose veins in your bottom. They can be outside the anus or inside the anus, and essentially can either be silent, in other words, you don’t know that you have them, or can present as pain, bleeding, itch, and can cause a lot of discomfort, particularly if one thrombosis.
So if you get a clot, it’s not life-threatening, but if you get a clot in a hemorrhoid, it can be very painful and require reasonably urgent therapy, so that you’re relieved of the pain.
The causes are really, it’s not really known but it certainly seems to be more common in Western countries, it’s thought to be increased risk in a diet that’s low in roughage, low in plant foods and vegetables, people who are prone to constipation and probably does run in families.
Dr Norman Swan, Physician and Journalist