Diverticula are small pouches that bulge outward through the colon, or large intestine. If you have these pouches, you have a condition called diverticulosis. It becomes more common as people age. About half of all people over age 60 have it. Doctors believe the main cause is a low-fiber diet.
Most people with diverticulosis don't have symptoms. Sometimes it causes mild cramps, bloating or constipation. Diverticulosis is often found through tests ordered for something else. For example, it is often found during a colonoscopy to screen for cancer. A high-fiber diet and mild pain reliever will often relieve symptoms.
If the pouches become inflamed or infected, you have a condition called diverticulitis. The most common symptom is abdominal pain, usually on the left side. You may also have fever, nausea, vomiting, chills, cramping, and constipation. In serious cases, diverticulitis can lead to bleeding, tears, or blockages. Your doctor will do a physical exam and imaging tests to diagnose it. Treatment may include antibiotics, pain relievers, and a liquid diet. A serious case may require a hospital stay or surgery.
NIH: National Institute of Diabetes and Digestive and Kidney Diseases