Does Oseltamivir Interact with Oseltamivir Phosphate?
Oseltamivir and Oseltamivir Phosphate have a major drug interaction according to U.S. FDA drug labeling data. 7 DRUG INTERACTIONS Live attenuated influenza vaccine (LAIV), intranasal: Avoid administration of LAIV within 2 weeks before or 48 hours after oseltamivir phosphate capsules use, unless medically indicated. ( 7 ) 7.1 Influenza Vaccines Live Attenuated Influenza Vaccine The concurrent use of oseltamivir phosphate capsules with live attenuated influenza vaccine (LAIV) intranasal has not been evaluated. However, because of the potential for oseltamivir phosphate capsules to inhibit replication of live vaccine virus and possibly reduce the efficacy of LAIV, avoid administration of LAIV within 2 weeks before or 48 hours after oseltamivir phosphate capsules administration, unless medically indicated. Patients taking both medications should consult their healthcare provider before starting, stopping, or changing the dosage of either drug. This information is based on official FDA drug labeling sourced from OpenFDA and the NIH National Library of Medicine.
- Severity
- Major
- Management
- Close medical supervision required
- Data Source
- U.S. FDA via OpenFDA
What To Tell Your Doctor or Pharmacist
If you are taking Oseltamivir and your doctor is considering prescribing Oseltamivir Phosphate (or vice versa), make sure to:
- Inform your doctor and pharmacist of all current medications, including over-the-counter drugs and supplements
- Ask whether the benefits of combining these medications outweigh the risks for your specific situation
- Ask what symptoms to watch for that would indicate the interaction is causing problems
- Ask how frequently you should be monitored while these are co-prescribed
- Ask whether any dosage adjustments are needed
- Never stop or change either medication without first consulting your healthcare provider