What should I do if I vomit everything I eat or drink?

Emergency Management of Persistent Vomiting

You need immediate medical evaluation, ideally in an emergency department, because inability to tolerate any oral intake represents severe dehydration requiring intravenous fluid resuscitation. 1

Immediate Actions Before Seeking Care

• Attempt small, frequent sips (not large volumes) of oral rehydration solution or clear fluids every 5-10 minutes while arranging transport to medical care 1, 2
• Do not attempt to force food or large volumes of liquid, as this will trigger more vomiting 2
• Monitor for signs of severe dehydration: decreased or absent urination, severe dizziness preventing standing, confusion, or altered mental status 3

What to Expect at the Emergency Department

Initial Stabilization

• Intravenous isotonic fluids (lactated Ringer's or normal saline) will be administered immediately because you cannot tolerate oral intake and likely have severe dehydration, shock risk, or electrolyte derangement 3, 1
• IV hydration continues until pulse, perfusion, and mental status normalize and you can tolerate oral intake without aspiration risk 3

Diagnostic Workup Required

The following tests must be obtained to identify the underlying cause 1, 4:

• Complete blood count to assess for infection or bleeding 1
• Serum electrolytes, glucose, kidney function to detect metabolic causes and assess dehydration severity 1
• Liver function tests and lipase to exclude hepatobiliary disease and pancreatitis 1, 4
• Calcium level to rule out hypercalcemia as a cause 1, 4
• Urinalysis and pregnancy test if applicable 1, 4
• Urine drug screen particularly for cannabis, as Cannabis Hyperemesis Syndrome is a common cause in younger adults 1

Imaging Studies

• Upper GI imaging or esophagogastroduodenoscopy (EGD) should be performed once to exclude mechanical obstruction, which is a critical diagnosis that changes management entirely 1, 4
• Patients unable to tolerate oral intake should not be discharged without imaging 4

Antiemetic Medication Protocol

First-Line Treatment

• Metoclopramide 10 mg IV every 6 hours is the initial antiemetic of choice, as it both controls vomiting and promotes gastric emptying 1, 2, 4
• Alternatively, prochlorperazine 10 mg IV every 6-8 hours can be used as a dopamine antagonist 1, 4

Second-Line Addition (if vomiting persists after 4 hours)

• Ondansetron 8-16 mg IV should be added, as it acts on different receptors (5-HT3) providing complementary coverage 1, 5
• Be aware ondansetron may increase diarrhea if gastroenteritis is the cause 3, 1
• Monitor for QT prolongation, especially if you have electrolyte abnormalities or heart conditions 5

Refractory Cases

• Haloperidol 1 mg IV every 4 hours as an alternative dopamine antagonist 1
• Dexamethasone 10-20 mg IV combined with ondansetron for superior efficacy 1
• Antiemetics should be given on a scheduled basis, not as needed, since prevention is more effective than treating established vomiting 1

Critical Conditions to Exclude

Mechanical Bowel Obstruction

• Never use antiemetics if bowel obstruction is suspected, as this masks progressive ileus and gastric distension 1, 5
• Signs include severe abdominal pain, distension, absence of bowel sounds, or peritoneal signs 4, 5

Cannabis Hyperemesis Syndrome

• Suspect if you have heavy cannabis use history preceding symptom onset 1
• Definitive diagnosis requires 6 months cannabis cessation or 3 typical cycle lengths without vomiting 1
• Treatment still works even with ongoing use, so do not delay seeking care 1

Volume Depletion Assessment

• Postural pulse increase ≥30 beats per minute or severe postural dizziness preventing standing indicates significant blood/fluid loss 3
• Four or more of these signs indicate moderate-to-severe volume depletion: confusion, non-fluent speech, extremity weakness, dry mucous membranes, dry tongue, furrowed tongue, sunken eyes 3

Special Considerations

Thiamin Supplementation

• If vomiting persists beyond 2-3 weeks, thiamin supplementation is mandatory to prevent Wernicke's encephalopathy 1, 2

Monitoring for Complications

• Watch for extrapyramidal symptoms (muscle rigidity, tremor, abnormal movements) with dopamine antagonists, particularly if you are a young male 1
• Treat immediately with diphenhydramine 50 mg IV if these develop 1

When Obstruction is Ruled Out

• Once mechanical causes are excluded, add a proton pump inhibitor if dyspepsia is present, as heartburn may be confused with nausea 1, 4
• Resume age-appropriate diet immediately after rehydration is complete 3

Do not delay seeking emergency care—complete inability to tolerate oral intake for any duration requires immediate IV fluid resuscitation and diagnostic workup to prevent life-threatening complications.