Hello! Thank you for the query. The most often reason of such strong pain is urinary tract stones. The symptoms do occur suddenly, the pain radiates to the back or the groin and usually is localized on the one side of the body. Frequent urinating or burning when urinating can be present as well. However urinary stones are not related to bowel movements, it can affect it. Other reason of such symptoms can be gallstones. The pain appears after a meal, can radiate to the back with nausea and vomiting. Such symptoms can be also caused by intestines obstruction due to colon cancer, peptic ulcers, diverticulitis, pancreas disease, anal fissure and many more. It is advisable for your husband to have some diagnostics starting with abdominal ultrasound, full blood work with liver and pancreas tests, urine analysis, occulted fecal blood test. If no findings in this tests, some other might be necessary like colonoscopy, upper GI endoscopy and abdominal CT. Hope this will help. Regards.