Peptic ulcer is a disorder of the digestive system that causes inflammation and lesions in different regions of the gastrointestinal tract. The disorder involves erosion of the mucus-covered protective surface of either the stomach or the duodenum.

Most peptic ulcers occur on the premises of genetically inherited physiological abnormalities, such as: inappropriate production of mucus (a natural protective substance that surrounds the internal soft tissues and organs), inappropriate production of bicarbonate (a chemical that neutralizes the effects of digestive acids) and poor blood circulation at the level of the stomach.

The major cause of peptic ulcer is infection with a type of bacterium called Helicobacter pylori. Although there are various other factors that contribute to the development of peptic ulcer, the disorder generally occurs as a consequence of infection with Helicobacter pylori bacteria. These bacteria weaken the internal organs' protective walls, allowing gastric acids and pepsin to cause serious damage to soft tissues and organs.

Another cause of peptic ulcer is the stomach's overproduction of digestive fluids. In normal amounts, gastric acid and pepsin have a very important role in the process of digestion. However, when the stomach secretes these substances in excess, they can cause ulcerations and lesions to the internal tissues and organs.

Research results indicate that smokers are exposed to a very high risk of developing peptic ulcers. Smoking increases the stomach's production of digestive fluids, thus facilitating the occurrence of the disorder. Furthermore, smoking slows down the healing of existing peptic ulcers and increases the risk of complications. Similar to smoking, caffeine can also lead to an overproduction of pepsin and stomach acid, thus contributing to the occurrence of peptic ulcer.

The excessive consumption of alcohol also greatly contributes to the development of peptic ulcer. Statistics indicate that peptic ulcer is very common among people who suffer from cirrhosis, a disease associated with the abuse of alcohol.

Studies in the field have found that certain oral medications are also a potential cause of peptic ulcer. Commonly prescribed in the treatment of rheumatoid arthritis, non-steroidal anti-inflammatory drugs have various side-effects at the level of the gastrointestinal system, and they greatly contribute to the occurrence of peptic ulcer. Ongoing treatments with aspirin, ibuprofen and naproxen interfere with the normal activity of the stomach in several different ways: they slow down the stomach's production of mucus and bicarbonate; they stimulate an overproduction of pepsin and gastric acid; they perturb the blood circulation in the lining of the stomach.

Emotional stress also seems to affect the activity of stomach, increasing the risk of developing peptic ulcer. Although medical scientists haven't established clear connections between emotional stress and peptic ulcer, it seems that people with emotional problems are commonly confronted with gastrointestinal disorders.

By contrast, physical stress has been confirmed to be a major cause of peptic ulcer. People who have acquired stomach injuries or people who have suffered surgical interventions are exposed to a high risk of developing peptic ulcer.