Symptoms You can get sick with food poisoning after swallowing certain germs, like  Salmonella  or  E. coli . Your symptoms may vary, depending on the germ you swallowed. Symptoms can range from mild to serious and can last for a few hours or several days. The most common symptoms of food poisoning are: Diarrhea Stomach pain or cramps Nausea Vomiting Fever If you have diarrhea or vomiting , be sure to drink plenty of fluids to prevent dehydration (not having enough water in your body). Complications and when to seek help Seek help See a doctor if you have any symptoms that are severe, including: Bloody diarrhea Diarrhea that lasts more than 3 days High fever (temperature over 102°F) Vomiting so often that you cannot keep liquids down Signs of dehydration, which include not urinating (peeing) much, a dry mouth and throat, and/or feeling dizzy when standing up See your doctor if you are pregnant and have a fever and other flu-like symptoms. Some mild infections can c...