Hemorrhoids are blood vessels (veins) in the anal canal. When those blood vessels become swollen or dilated, symptoms may develop. Many people have hemorrhoids, but have no symptoms.
Hemorrhoids are very common and by age 50, nearly half of Americans have hemorrhoids. Nearly 5% of the US population (15,000,000 people) has sought medical care for symptomatic hemorrhoids. Many more have problems with hemorrhoids, but never seek formal medical attention.
External hemorrhoids may be present and cause no symptoms. When they cause symptoms, the most common are pain, itching, pressure and bleeding; they can often be felt as a bulge in the skin near the anal opening.
Internal hemorrhoids may be present and cause no symptoms. When they cause symptoms, the most common are painless rectal bleeding, which usually is seen as bright red blood on the toilet paper or in the toilet bowl. It is important to know that just a few drops of blood in toilet water can change the color of the water dramatically.