﻿ Nausea and Vomiting Symptoms, Causes, Treatment - How is the
source of nausea or vomiting diagnosed? - MedicineNet  Nausea
and Vomiting (cont.)  Medical Author: Medical Editor:  How is
the source of nausea or vomiting diagnosed?  Diagnosis often can
be made when the health care professional takes a careful
history and performs a physical examination. Any tests that need
to be ordered will be based on the direction from the history
and physical exam, and sometimes no further testing is required
to make the diagnosis.  Laboratory tests and X-rays may be
ordered to assess the stability of the patient and not
necessarily to make the diagnosis. For example, a patient with
food poisoning may need blood tests ordered to measure the
electrolytes and other chemicals, since the patient may lose
significant amounts of sodium, potassium, and chloride from the
body from persistent vomiting and diarrhea.  Urinalysis may be
helpful in assessing hydration status. Concentrated, dark urine
is associated with dehydration beca