What is the appropriate management for a 62-year-old female patient with fever, nausea, and vomiting, who recently completed chemotherapy (chemo) for lung cancer 3 days ago?

Management of Post-Chemotherapy Fever, Nausea, and Vomiting in a 62-Year-Old Woman with Lung Cancer

This patient requires immediate evaluation for febrile neutropenia with complete blood count and blood cultures, while simultaneously treating her nausea and vomiting with intravenous antiemetics, as she is presenting 3 days post-chemotherapy—the peak timing for both drug fever and infectious complications.

Immediate Priority: Rule Out Febrile Neutropenia

Fever occurring 3 days after chemotherapy is the most critical timeframe for both drug-induced fever and febrile neutropenia, requiring urgent assessment. 1

• Fever on posttreatment days 3 and 4 occurs most frequently after chemotherapy, with day 4 showing the highest incidence (8%) followed by day 3 (7%) 1
• The causes of post-chemotherapy fever include:
  • Infection (47%), including febrile neutropenia (24%) 1
  • Adverse drug effects/drug fever (24%) 1
  • Unknown causes (19%) 1
  • Tumor-related (7%) 1

Essential Workup

• Complete blood count with differential to assess for neutropenia (absolute neutrophil count <500 cells/μL or <1000 cells/μL with predicted decline) 1
• Blood cultures (aerobic and anaerobic) from peripheral and central lines if present 1
• Chest X-ray given her lung cancer diagnosis and respiratory infection risk 1
• Urinalysis and urine culture 1
• Metabolic panel to assess for electrolyte disturbances that can contribute to nausea 2

Critical Clinical Decision Point

If febrile neutropenia is confirmed (fever + ANC <500), initiate broad-spectrum antibiotics immediately—this is a medical emergency with significant mortality risk. The nausea and vomiting management becomes secondary to infection control in this scenario. 1

Management of Nausea and Vomiting

Immediate Treatment (Breakthrough/Refractory CINV)

Since the patient is actively vomiting, all antiemetics must be administered intravenously, not orally. 2, 3

This represents delayed chemotherapy-induced nausea and vomiting (CINV), occurring >24 hours after chemotherapy completion. 2

First-Line IV Antiemetic Regimen

• Ondansetron 8 mg IV administered immediately 3, 4
• Dexamethasone 8 mg IV twice daily for delayed emesis 2, 3
• Consider adding metoclopramide (dopamine antagonist) if the above combination fails 3

The combination of 5-HT3 antagonist (ondansetron) plus corticosteroid is the standard approach for breakthrough CINV. 2, 3

If Initial Therapy Fails (Refractory CINV)

For patients who fail conventional antiemetic therapy, cannabinoids (nabilone or dronabinol) should be considered as rescue therapy. 5

• The American Society of Clinical Oncology recommends either dronabinol or nabilone for rescue and refractory CINV 5
• This is appropriate when standard 5-HT3 antagonists, NK1 antagonists, and corticosteroids have been inadequate 5

Prophylaxis for Future Chemotherapy Cycles

For her next chemotherapy cycle, prophylactic antiemetics should be given 30-60 minutes before chemotherapy administration to prevent recurrence. 2, 3

The specific regimen depends on the emetogenicity of her lung cancer chemotherapy:

• Highly emetogenic (e.g., cisplatin ≥50 mg/m²): 5-HT3 antagonist + NK1 antagonist + dexamethasone 2, 3
• Moderately emetogenic (e.g., carboplatin): 5-HT3 antagonist + dexamethasone 2, 3

Other Differential Diagnoses to Consider

Beyond infection and drug fever, evaluate for: 2

• Gastrointestinal obstruction (especially with nausea/vomiting; perform abdominal exam and consider imaging if indicated) 2
• Brain metastases (assess for headache, neurologic symptoms) 2
• Hypercalcemia (check calcium level) 2
• Constipation (common with antiemetics and opioids if prescribed) 2
• Concurrent medications (opioids, antibiotics, antifungals can cause nausea) 2

Common Pitfalls to Avoid

• Never assume fever is "just drug fever" without ruling out infection first—infection accounts for nearly half of post-chemotherapy fevers, and febrile neutropenia is life-threatening 1
• Do not give oral antiemetics to actively vomiting patients—they will not be absorbed; use IV route 2, 3
• Do not use the same antiemetic regimen that failed—if breakthrough CINV occurs despite prophylaxis, escalate therapy or add different drug classes 2, 3
• Younger women are more prone to nausea than other populations—this 62-year-old woman may need more aggressive antiemetic management 2

Disposition

• Admit if febrile neutropenia confirmed for IV antibiotics and monitoring 1
• Admit if unable to tolerate oral intake due to persistent vomiting (risk of dehydration and electrolyte abnormalities) 2
• Outpatient management possible if infection ruled out, fever is drug-related, and vomiting controlled with IV antiemetics with plan for close follow-up 1