Irritable bowel syndrome and lactose intolerance are causes of chronic abdominal pain, according to WebMD and Healthline. Crohn's disease, a condition that inflames the bowel, causes chronic abdominal pain, reports the National Institutes of Health.
Irritable bowel syndrome causes abdominal cramps and discomfort in the lower abdomen, reports WebMD. These symptoms typically worsen after eating and subside following a bowel movement. Additionally, diarrhea, constipation, gas and abdominal distension are common symptoms of IBS. Some medical scientists believe IBS is caused by abnormal contractions of the bowel muscles, although the condition is not entirely understood.
Lactose intolerance causes nausea, bloating and gas production as a result of bacterial fermentation in the colon, explains Healthline. This condition occurs each time lactose is consumed and causes some of the same symptoms as Crohn’s disease, such as abdominal pain, cramps and diarrhea. Lactose intolerance occurs in people who are deficient in an enzyme called lactase. This enzyme is necessary to break down lactose, a simple sugar found in dairy products. Lactose intolerance is treatable and is not considered a serious health condition.
Crohn's disease is a chronic inflammatory bowel disease that typically gets worse over time. This disease is characterized by abdominal pain due to inflammation, swelling and irritation in the gastrointestinal tract, reports the National Institutes of Health. Fatigue, joint pains, skin changes, anemia and weight loss are other symptoms of Crohn’s disease. Although the exact cause of the disease is unknown, scientists believe an autoimmune reaction, genetics and certain medications can increase the risk of getting Crohn’s disease.