What Is Diarrhea?

Diarrhea is the frequent passage of loose, watery, soft stools plus bloating pressure, and cramps.

Viral infections are the cause of most cases with mild-to-moderate symptoms (such as nausea). Bacterial infections cause the more serious cases, typically from contaminated foods or drinks (food poisoning). Bacterial infections also cause severe symptoms with vomiting, fever, and severe abdominal cramps or pain.

In more serious cases, the stool may contain mucus, pus, or bright red blood.