Gastric erosion

Gastric erosion occurs when the mucous membrane lining the stomach becomes inflamed. Some drugs, as tablets, can irritate this mucous membrane, especially drugs taken for arthritis and muscular disorders, steroids, and aspirin. A gastric erosion may also occur because of emotional stress, or as a side effect of burns or stomach injuries.

Symptoms
There is basically one symptom of gastric erosion: bleeding from the area where the stomach lesion is. Bowel movements may contain blood. Vomit may be bloody as well, but a gastric erosion may not cause vomiting. Blood may be black because it will be partially digested. Loss of blood may cause one to develop anemia. Tell your doctor if you are taking a pain reliever or a drug to prevent arthritis and feel abnormally fatigued, vomit blood, have severe indigestion, or have black bowel movements.

Risks
Anemia and other problems related to blood loss may occur. Sometimes a person with a gastric erosion will experience severe bleeding all at once; here red (bloody) vomiting may occur, and/or black bowel movements.

Treatment
Doctors can prescribe alternative anti-arthritic drugs, and alternatives for aspirin are available. Once you have gastric erosion, however, you cannot treat it without the aid of a physician. To keep from getting gastric erosion, drugs that could irritate your stomach should be taken with (or directly after) food. Those with severe gastric erosion will likely be hospitalized and given a blood transfusion. Unless there is an underlying disease causing gastric erosion, once the irritant is removed, gastric erosion will not occur again.

Source
"Gastric Erosion." Encyclopaedia Britannica, Micropaedia. Encyclopaedia Britannica Inc., 1998 ed.