I have nausea, gas, constipation for the past four months. I think that it can be due to food poisoning or stomach virus. I have done a CT, MRI brain, gastric emptying study, colonoscopy, and endoscopy. All the results were normal. All the blood tests were normal. I had an abnormal level of fecal calprotectin and it was 280 mcg/g. Now, it has gone down to 9 mcg/g. Could I have a problem with the functions of the gall bladder? I have lost ten kilograms and I am 19 years old. My appendix has been removed and I am taking Ondansetron for nausea and it does not work.