Most physicians recognize that the ingestion of lye is associated with severe esophageal damage. It is much less widely known that gastric injury is the predominant finding when acid is ingested. We are reporting on five patients who had severe gastric damage after ingestion of diluted sulfuric acid (three cases), capsules of potassium hydroxide, and Clinitest tablets (one case each). Fiberoptic endoscopy was used to localize the extent and severity of injury and to follow the evolution of the damage. The extent and location of injury varied with the amount and type of agent ingested. Acid ingestion resulted in severe gastritis, which eventually led to antral stenosis and gastric outlet obstruction requiring operative intervention in two cases. Potassium hydroxide capsules produced diffuse esophagitis, gastritis, and a non-healing large gastric ulcer. Clinitest tablets produced distal esophagitis and stricture and antral damage leading to gastric outlet obstruction which required operative intervention. These cases demonstrate the natural history of corrosive injury to the stomach and the value of fiberoptic endoscopy in the management of this problem.