Hi There For The Last 12 Yrs From Time To

Hi there for the last 12 yrs from time to time i get a bad abdominal pain which lasts for a few days it is a burning stinging pain just under my rib cage (right side) sometimes radiating to my back and side as well. Did all the blood test for liver and pancreas all normal. Had a CT Scan and an ultrasound done few years back all ok, no gallstones no problem with kidneys, i Had a problem with acid reflux but that is under control , i do get an endoscopy procedure done every three years, I had an endoscopy procedure in May 2016 and all the biopsy results were ok . All the doctors and specialist have ruled any major complication Any advise ? And yes I don't smoke social drinker Fit do workout 4-5 days a week active and 45 yrs old not overweight