Chronic abdominal pain Fortunately, in most of cases the chronic abdominal pain is not caused by severe illness, but it can be depressing if the abdomen is always painful. There are many problems that can cause abdominal pain. Smooth muscle is in the walls of hollow internal organs, such as the arteries, intestines, bladder in the abdomen. When they contract, the organ is squeezed. Most of the abdominal pain is visceral pain which is pain arising from the internal organs. Visceral pain is triggered by smooth muscle distension or contraction, stretching of the capsule surrounding an organ, ischaemia and necrosis, or irritation by chemicals produced during inflammatory processes. If stomach or intestine wall becomes spasm, this may result in pain. So do kidneys, gallbladders and other internal organs. When the uterine smooth muscle becomes spasm, menstrual cramps occur. It is often deep, dull or dragging and is typically diffuse and poorly localised. It can be associated with nauseas, vo...