Nausea and vomiting

Your health care provider will perform a physical examination, particularly to look for signs of dehydration.

To help diagnose the cause of the nausea or vomiting, your doctor will ask medical history questions, such as:

Are you vomiting fresh blood? Do you have repeated episodes of vomiting blood?
Are you vomiting material that looks like coffee grounds?
Are you vomiting undigested food?
Are you vomiting greenish material?
Is the nausea or vomiting severe enough to cause unintentional weight loss?
Is the vomiting self-induced?
Have you been traveling? Where?
What medications do you take?
Did other people that ate at the same location as you have the same symptoms?
Are you pregnant or could you be pregnant?
When did the vomiting begin? How long has it lasted?
Does it occur several hours after meals?
What other symptoms are also present -- abdominal pain, fever, diarrhea, poor skin turgor, other signs of dehydration, abdominal swelling, headaches?

The following diagnostic tests may be performed:

Blood tests (such as CBC with differential and basic electrolytes)
Urinalysis
X-rays of the abdomen

If dehydration is severe, you may need intravenous fluids. This may require hospitalization, although it can often be done in the doctor's office. The use of antivomiting drugs (anti-emetics) is controversial, and they should be used only in severe cases.

Prevention:

A number of medicines are effective at preventing vomiting. Your doctor is unlikely to prescribe these because, in most situations, the vomiting is an important part of getting well. In some situations, however, preventing the vomiting makes life much better.

References:

Koch KL. Nausea and vomiting during pregnancy. Gastroenterol Clin North Am. 2003; 32(1): 201-234, vi.

Quigley EM. AGA technical review on nausea and vomiting. Gastroenterology. 2001; 120(1): 263-286.