What are the recommended treatments and next steps for an adult patient with no significant past medical history presenting with nausea, vomiting, and a mild temperature?

Management of Nausea, Vomiting, and Mild Temperature in Adults

For an adult with nausea, vomiting, and mild fever without significant past medical history, start with a dopamine receptor antagonist (metoclopramide 10-20 mg or prochlorperazine 5-10 mg every 6 hours) on a fixed schedule, ensure adequate hydration, and evaluate for common infectious causes like gastroenteritis while monitoring for alarm symptoms that would require urgent evaluation. 1

Initial Assessment and Risk Stratification

Determine symptom acuity and severity immediately:

• Acute symptoms (lasting less than 7 days) with mild fever most commonly indicate viral gastroenteritis, foodborne illness, or other self-limiting viral syndromes 2
• Check for alarm symptoms requiring hospitalization: severe dehydration, inability to tolerate oral fluids, severe abdominal pain, altered mental status, or signs of intestinal obstruction 3
• In elderly patients or those from long-term care facilities, fever with nausea/vomiting may indicate bacteremia—look for hypotension, shaking chills, or band neutrophil count >1,500 cells/mm³ 4

Key historical features to elicit:

• Timing: Early morning episodes suggest cyclic vomiting syndrome; prodromal symptoms (sense of doom, anxiety, mental fog) lasting about 1 hour before vomiting onset support this diagnosis 4
• Triggers: Stress (70-80% of cyclic vomiting cases), sleep deprivation, menstrual cycle, recent infections, or surgery 4
• Medication review: Recent antibiotic starts (especially vancomycin), statins, or any new medications 5, 6
• Associated symptoms: Abdominal pain is present in most cyclic vomiting episodes and should not exclude this diagnosis; look for stereotypical clustering of symptoms like diaphoresis, flushing, headache, or bowel urgency 4

First-Line Pharmacologic Management

Initiate antiemetic therapy on a fixed schedule, not as-needed:

• Metoclopramide 10-20 mg PO/IV every 6 hours OR prochlorperazine 5-10 mg PO/IV every 6 hours 1
• Fixed scheduling maintains constant therapeutic levels and prevents emetic episodes more effectively than PRN dosing 1
• For mild acute gastroenteritis without severe dehydration, empiric antiemetic therapy is appropriate without extensive testing 3, 2

Supportive care:

• Fluid and electrolyte replacement—oral rehydration preferred if tolerated 2
• Small, frequent meals rather than large meals 1
• Cold foods better tolerated than hot foods due to less strong aromas 1

Escalation for Persistent Symptoms (24-48 Hours)

If symptoms persist despite first-line therapy:

• Add ondansetron 4-8 mg PO/IV every 8-12 hours (5-HT3 antagonist) 1, 7
• Consider adding dexamethasone 4-8 mg PO/IV daily to potentiate antiemetic effect 1
• For suspected cyclic vomiting syndrome in prodromal phase, early abortive therapy has higher success rates—educate patients to self-administer at symptom onset 4

Common pitfalls to avoid:

• Do not start with high doses in elderly patients; begin with reduced doses (e.g., metoclopramide 5-10 mg) 1
• Monitor for extrapyramidal symptoms with metoclopramide and prochlorperazine; have diphenhydramine 50 mg available for dystonic reactions 1
• Be aware that 5-HT3 antagonists like ondansetron can cause QT prolongation—avoid in patients with congenital long QT syndrome and monitor ECG in those with electrolyte abnormalities 7

When to Pursue Further Evaluation

Obtain basic laboratory testing if:

• Symptoms persist beyond 7 days (transition to chronic nausea/vomiting) 2
• Severe metabolic abnormalities suspected (check basic metabolic panel) 3
• Fever persists or worsens, suggesting bacterial infection rather than viral syndrome 4
• Patient appears severely ill or has signs of bacteremia (hypotension, altered mental status, severe abdominal pain) 4

Consider cyclic vomiting syndrome if:

• Stereotypical episodes of acute-onset vomiting lasting <7 days 4
• At least 3 discrete episodes in a year with 2 in prior 6 months, separated by at least 1 week of baseline health 4
• Personal or family history of migraine headaches (supportive criterion) 4
• If cyclic vomiting suspected, refer to gastroenterology for specialized management including prophylactic therapy 4

Refractory Cases

For symptoms not responding to dopamine antagonist plus 5-HT3 antagonist:

• Olanzapine 2.5-5 mg PO daily is particularly effective for refractory nausea 1
• Lorazepam 0.5-1 mg PO/IV every 4-6 hours for anxiety-related component 1
• Consider continuous IV/subcutaneous infusion if oral route not tolerated 1

Reevaluate within 24-48 hours:

• Assess hydration status, ability to tolerate oral intake, and symptom control 1
• If no improvement, broaden differential to include gastroparesis, intestinal obstruction, CNS causes, metabolic disorders, or medication-induced causes 3, 2