Vomiting, along with nausea, is a symptom of an underlying disease rather than a specific illness itself. Emesis is the medical term for vomiting. Vomiting is the forcible emptying of the stomach in which the stomach has to overcome the pressures that are normally in place to keep food and secretions within the stomach. Causes of vomiting are varied and include food-borne illnesses (food poisoning), infections, problems with the brain and central nervous system, and systemic (body-wide) diseases. Some illnesses will cause nausea and vomiting, even though there is no direct involvement of the stomach or gastrointestinal tract. Examples can include pneumonia, heart attack, and sepsis. Vomiting may be a side effect of medications, including drugs used in cancer chemotherapy, as well as a side effect of radiation therapy.

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