Husband ate lunch at local Mexican restaurant Within one hour felt bloating and very full, then became nauseous. Vomiting and diarrhea at the same time about 12 hours later with soaking sweat but feeling hot. Now two days later he feels weak, light headed, an still not eating much. Is this likely to be food poisoning and what should he do. I worry he may be dehydrated. He is 71 years old and in good health otherwise.