Brief Answer:
A number of causes are possible.

Detailed Answer:
Thanks for asking on HealthcareMagic.

I have gone very carefully through your query. Your problem could either be due to food poisoning or due to gastroesophageal reflux. Our gastrointestinal tract has a forward propulsive movement (peristalsis) that moves the food material forward as it is digested, absorbed and finally expelled as feces. If somehow this movement gets hampered, food along with the digestive juices would stagnate, stomach acid will reflux into the food pipe and you would feel nauseous. Ideally you need to be examined clinically to rule out other possible causes of nausea.

In order to relieve yourself, you need to do the following:
* Avoid spicy food. Take small but frequent meals. Avoid long gaps between meals.
* Avoid alcohol intake (if it a part of your habit).
* Take Prilosec (omeprazole) once daily before breakfast.
* Take some over the counter antiemetic like meclizine, cyclizine, dimenhydrinate or diphenhydramine when needed.
* Regular morning walk and exercise to keep the bowel movements proper.
* Take curd or yogurt on daily basis. It contains beneficial bacteria and should help.
* Take ORS (oral rehydration solution) if you have vomiting.

Hope that helps. If it still does not help, it would be a good idea to visit your doctor.

Let me know if I could help further.

Regards

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