Hi
Welcome to the MedHelp forum!
Commonest cause of chronic nausea is acidity. Take omeprazole (empty stomach in morning) and antacid gel and see if it helps. Liver and kidney dysfunction is another cause. Hence kidney and liver function tests should be done. Other causes are diabetes and hypothyroidism. Electrolyte imbalance too can cause nausea. IBS, gluten or lactose intolerance, parasites in gut too can be the cause. A stool test should be done for worms, giardiasis etc. Chronic hepatitis or chronic infection of the gall bladder is the other possibilities. Also if nothing is found then food challenge test to detect food intolerance should be done. Chronic constipation, sedentary life style building up gas in the gut, inflammatory bowel disease, food rich in sulfites (molasses, dry powder, pickles, tinned shrimp, cookies, crackers, and readymade pie dough), cabbage, raddish etc also cause bloating and nausea.
The best thing would be to consult a general practitioner or PCP and try and assess what is the cause of your problem. Then proper referral for concerned specialist can take things further and get you proper treatment. Take care!
Are you having constipation when they happen? Have they ever taken a look at how your gallbladder is functioning? If you stop and take time to think about it, are you under a lot of stress? Do you feel like you might be retaining water?