Ulcer

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Ulcer, shallow sore produced by the destruction of skin or mucous membrane. Skin ulcers may occur in association with a number of chronic illnesses, such as diabetes, kidney and heart ailments, varicose veins, syphilis, leprosy, tuberculosis, and cancer. Gastrointestinal ulcers occur with chronic gastritis, ulcerative colitis, and typhoid fever.

Peptic ulcers are ulcers of the stomach (gastric) or small intestine (duodenal). In addition to the pain caused by the ulcer itself, peptic ulcers give rise to such complications as hemorrhage from the erosion of a major blood vessel; perforation of the wall of the stomach or intestine, with resultant peritonitis; or obstruction of the gastrointestinal tract because of spasm or swelling in the area of the ulcer.

The direct cause of peptic ulcers is the destruction of the gastric or intestinal mucosal lining by hydrochloric acid, an acid normally present in the digestive juices of the stomach. Infection with the bacterium Helicobacter pylori is thought to play an important role in causing both gastric and duodenal ulcers. Injury of the gastric mucosal lining, and weakening of the mucous defenses such as by nonsteroidal anti-inflammatory drugs, are also responsible for gastric ulcer formation. Excess secretion of hydrochloric acid, genetic predisposition, cigarette smoking, and psychological stress are important contributing factors in duodenal ulcer formation and exacerbation.

Several different types of prescription drugs are used in the treatment of ulcers. Antacids may be ingested to neutralize the hydrochloric acid secretions. Drugs such as cimetidine and ranitidine block the action of histamine, the body chemical that triggers acid secretion, and have been shown to induce healing of ulcers in many patients. Omeprazole inhibits acid secretion by disabling the cellular pumps that pump acid into the stomach. Bismuth-containing compounds and antibiotics may be used to eradicate Helicobacter pylori infection, accelerating healing and reducing the rate of ulcer recurrence. Sucralfate forms a protective layer that enhances the mucosal lining of the stomach and intestines. Misoprostol is effective against gastric ulcers caused by nonsteroidal anti-inflammatory drugs. Quitting smoking can also accelerate the healing process. Alcohol and caffeine should be avoided, although in general a bland diet is of no benefit. In extreme cases surgery may be required.

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