Can Ondansetron (Zofran) Be Given with Bupropion (Wellbutrin)?
Yes, ondansetron can be safely given to patients taking bupropion—there is no contraindication or clinically significant drug interaction between these medications.
Key Safety Considerations
The FDA drug label for bupropion (Wellbutrin) does not list ondansetron as a contraindicated medication or problematic drug interaction 1. The primary drug interaction concerns with bupropion involve:
- MAO inhibitors (contraindicated due to hypertensive crisis risk)
- Drugs metabolized by CYP2D6 (bupropion inhibits this enzyme)
- Medications that lower seizure threshold (requires caution with antipsychotics, other antidepressants, theophylline, systemic corticosteroids)
- Dopaminergic drugs like levodopa and amantadine (CNS toxicity risk)
Ondansetron does not fall into any of these problematic categories 1.
Clinical Context from Guidelines
Multiple clinical practice guidelines recommend ondansetron for various indications without any warnings about bupropion co-administration:
- ASCO antiemetic guidelines extensively detail ondansetron dosing for chemotherapy-induced nausea/vomiting with no mention of bupropion interactions 2, 3
- NCCN smoking cessation guidelines discuss both bupropion (for smoking cessation) and ondansetron separately without contraindication warnings 4
- AGA pregnancy guidelines recommend ondansetron for hyperemesis gravidarum as second-line therapy without bupropion interaction concerns 5
Theoretical Pharmacologic Considerations
While one older study suggested that SSRI antidepressants (specifically fluoxetine) might theoretically reduce ondansetron's antiemetic efficacy through serotonin reuptake inhibition competing at 5-HT3 receptors 6, this concern does not apply to bupropion. Bupropion is a norepinephrine-dopamine reuptake inhibitor, not a serotonin reuptake inhibitor 7. It does not affect serotonin pathways in a way that would interfere with ondansetron's 5-HT3 receptor antagonism.
Practical Prescribing Guidance
You can prescribe ondansetron to patients on bupropion without dose adjustments or special monitoring beyond standard precautions for each medication individually:
- Monitor for bupropion's seizure risk (especially with doses >450 mg/day, history of eating disorders, alcohol withdrawal) 1
- Monitor for ondansetron's common side effects (headache, constipation, potential QT prolongation at high doses)
- No specific drug-drug interaction monitoring is required
The combination is commonly used in clinical practice, particularly in oncology patients receiving chemotherapy who may also be treated with bupropion for depression or smoking cessation 4, 2, 3.