If you experience any of the following signs or symptoms, seek medical attention. Frequent episodes of vomiting and inability to keep liquids down Bloody vomit or stools Diarrhea for more than three days Extreme pain or severe abdominal cramping An oral temperature higher than 100.4 F (38 C) Signs or symptoms of dehydration — excessive thirst, dry mouth, little or no urination, severe weakness, dizziness, or light-headedness Neurological symptoms such as blurry vision, muscle weakness and tingling in the arms