Four clinical types of diarrhoea can be recognized:
* Acute watery diarrhoea (including cholera): This lasts several hours or days, the main danger is dehydration, weight loss also occurs if feeding is not continued.
* Acute bloody diarrhoea: This is also called dysentery, the main dangers are intestinal damage, sepsis and malnutrition; other complications, including dehydration, may also occur.
* Persistent diarrhoea: This lasts 14 days or longer, the main danger is malnutrition and serious non-intestinal infection; dehydration may also occur.
* Diarrhoea with severe malnutrition: the main dangers are severe systemic infection, dehydration, heart failure and vitamin and mineral deficiency.