The patient typically seeks medical care 1 to 6 hours after eating because of severe nausea, vomiting, retching, and abdominal cramps that may progress later into diarrhea. Patients may present with a wide range of findings. Signs and symptoms can range from mild to severe illness. It begins with minor nausea, vomiting, malaise, and diarrhea, progressing to conditions where patients may appear very ill: pale, diaphoretic, tachycardic, orthostatic, and perhaps complaining of paresthesias.

 

Others may have similar symptoms from eating the same food. The physical examination, however, is often reassuring. There is minimal abdominal tenderness, localized, if at all, to the epigastrium or to the rectus abdominis muscle (which is strained by the vomiting).