Stomach ailments are a group of medical conditions that affect the digestive system. ULCER, gastritis, and COLIC are three common stomach ailments. An ULCER is an open sore in the lining of the stomach or small intestine. Gastritis is an inflammation of the stomach lining that can cause pain, nausea, and vomiting. COLIC is a condition characterized by abdominal pain, cramping, and bloating. All three of these ailments can be treated with medication and lifestyle changes.