An ulcer is an erosion of the top layer of cells from an area, such as the wall of the stomach or duodenum. This erosion leaves the underlying layers of cells unprotected and exposed to gastric juices. The erosion may proceed until the gastric juices reach the capillaries that feed the area, leading to bleeding, and reach the nerves, causing pain. If Gl bleeding is excessive, iron deficiency may develop. If the erosion penetrates all the way through the Gl lining, a life-threatening infection can develop. Many people naively believe that an ulcer is caused by stress or spicy foods, but this is not the case - at least not at first. The stomach lining in a healthy person is well protected by its mucous coat. What, then, causes ulcers to form? Three major causes of ulcers have been identified: bacterial infection with Helicobacter pylori, the use of certain anti-inflammatory drugs such as ibuprofen and naproxen, and disorders that cause excessive gastric acid secretion. The cause of the ulcer dictates the type of drug treatment. For example, people with ulcers caused by infection receive antibiotics, whereas those with ulcers caused by drugs discontinue their use. In addition, all treatments plans aim to relieve pain, heal the ulcer, and prevent recurrence.