Hi. Thanks for your query. This is neither due to high blood pressure nor due to the tablets. The pain in abdomen which causes the person to be pale and ill; and makes one stand bent over is a serious pain. Unless proved otherwise this indicates that there is an inflammatory process going on in the abdomen like appendicitis or so. He needs to see a Surgeon immediately , to be examined by the Specialist to see there is tenderness and rebound tenderness. undergo immediate investigations as 2 days have already gone with the pain. Needs Standing X-ray abdomen to rule out gas under diaphragm, ultrasonography and may be a CT Scan to see what is wrong. He may need an urgent exploratory abdominal surgery.