A step wise approach is needed to diagnose pain under right rib cage (just below your right breast
—it may be on the flank side). If you have pain
under your right rib
then there could be a liver infection, pancreatitis, or a gall bladder problem. Get a liver function test, ultrasound or CT of abdomen, and pancreatic enzymes. It can also be due to acidity and duodenal ulcer. Take a late night snack. Raise head end of bed. Take Omeprazole empty stomach in morning and an antacid gel at bedtime.