External hemorrhoids are those that occur outside of the anal verge. They are usually painful, and are often accompanied by pruritus ani or an itching, swelling, and burning sensation. If the vein ruptures and a blood clot develops, the hemorrhoid becomes a thrombosed hemorrhoid. External hemorrhoids, which develop around the rim of the anus, are often fairly painful, because the skin around them is unusually sensitive.

External hemorrhoids sometimes rupture and bleed. When an external hemorrhoid becomes filled with a blood clot (thrombosed), it typically appears as a firm swelling or lump around the rim of the anus.

Internal hemorrhoids are those that occur inside the rectum. As this area lacks sensitive nerve endings, internal hemorrhoids are usually not painful and most people are not aware that they have them. Internal hemorrhoids, however, may bleed when irritated. Internal hemorrhoids, which develop inside the passageway of the anus, are usually painless, although they sometimes cause vague discomfort and minimal bleeding if a hard stool rubs against them during a bowel movement. Internal hemorrhoids also may protrude (prolapse) outside the anus, where they appear as small, grape-like masses. These can be painful.

Untreated internal hemorrhoids can lead to two severe forms of hemorrhoids: prolapsed and strangulated hemorrhoids. Prolapsed hemorrhoids are internal hemorrhoids that are so distended that they are pushed outside of the anus. If the anal sphincter muscle goes into spasm and traps a prolapsed hemorrhoid outside of the anal opening, the supply of blood is cut off, and the hemorrhoid becomes a strangulated hemorrhoid.

Diagnosis of Hemorrhoids
To diagnose hemorrhoids, the doctor will do a rectal examination. The doctor places a gloved and lubricated finger into the rectum to feel for abnormalities. External hemorrhoids can be diagnosed by a visual and/or rectal examination. To diagnose internal hemorrhoids, the doctor will insert a thin tube-like instrument (called an anoscope) into the lower few inches of the rectum. The anoscope has a light at the end and an eyepiece at the front for viewing into the anal canal. To look for other sources of bleeding, the doctor may perform a colonoscopy (an examination of the inside of the colon) or a sigmoidoscopy (an examination of the rectum and the last part of the colon - the sigmoid colon).

What is the treatment?
Medical treatment of hemorrhoids is aimed initially at relieving symptoms. Measures to reduce symptoms include soaking in tub baths several times a day in plain, warm water for about 10 minutes and the application of a hemorrhoidal cream or suppository to the affected area for a limited time.

Preventing the recurrence of hemorrhoids will require relieving the pressure and straining of constipation. Doctors will often recommend increasing fiber and fluids in the diet. Eating the right amount of fiber and drinking six to eight glasses of fluid-not alcohol-result in softer, bulkier stools. A softer stool makes emptying the bowels easier and lessens the pressure on hemorrhoids caused by straining. Eliminating straining also helps prevent the hemorrhoids from protruding.

Good sources of fiber are fruits, vegetables, and whole grains. In addition, doctors may suggest a bulk stool softener or a fiber supplement such as psyllium (Metamucil) or methylcellulose (Citrucel).In some cases, hemorrhoids must be treated endoscopically or surgically. These methods are used to shrink and destroy the hemorrhoidal tissue. The doctor will perform the procedure during an office or hospital visit.

A number of methods may be used to remove or reduce the size of internal hemorrhoids. These techniques include:
- Rubber band ligation: A rubber band is placed around the base of the hemorrhoid inside the rectum. The band cuts off circulation, and the hemorrhoid withers away within a few days.
- Sclerotherapy: A chemical solution is injected around the blood vessel to shrink the hemorrhoid.
- Infrared coagulation: A special device is used to burn hemorrhoidal tissue.
- Hemorrhoidectomy: Occasionally, extensive or severe internal or external hemorrhoids may require removal by surgery known as hemorrhoidectomy.