What should I do if I have food poisoning?

Depends on cause. Food poisoning may be due chemicals, bacterial toxins, bacterial and viral infections, and parasites. See this site for more info. http://www.webmd.com/food-recipes/food-poisoning/food-poisoning.
Variable response. Treatment of Food poisoning may include oral or intravenous replacement of fluids/ electrolytes. Antibiotics may be needed for bacterial infections. Hospitalization is sometimes necessary.

Related Questions

What should I do if I have got food poisoning?

This depends. Botulism is a form of food poisoning and you should probably see your doctor. Other types of food-poisoning are self-limited and get better with rest and liquids. Serious symptoms that should not be ignored include fever, worsening abdominal pain and blood in your stool. Read more...