Does Phenytoin Interact with Emtricitabine And Tenofovir Alafenamide?
Phenytoin and Emtricitabine And Tenofovir Alafenamide have a moderate drug interaction according to U.S. FDA drug labeling data. Decreases TAF concentration. Consider alternative anticonvulsant. The mechanism involves p-gp and bcrp induction leading to decreased taf absorption. 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
- Moderate
- Phenytoin Class
- Anti-epileptic Agent
- Emtricitabine And Tenofovir Alafenamide Class
- Human Immunodeficiency Virus Nucleoside Analog Reverse Transcriptase Inhibitor
- Management
- Monitor for effects
- Data Source
- U.S. FDA via OpenFDA
How This Interaction Works
The interaction between Phenytoin and Emtricitabine And Tenofovir Alafenamide occurs because p-gp and bcrp induction leading to decreased taf absorption. Clinically, this means decreases taf concentration. consider alternative anticonvulsant. This is classified as a moderate interaction. While it may not require stopping either medication, your healthcare provider should be aware you are taking both so they can monitor for potential effects and adjust treatment if necessary.
What To Tell Your Doctor or Pharmacist
If you are taking Phenytoin and your doctor is considering prescribing Emtricitabine And Tenofovir Alafenamide (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 whether any dosage adjustments are needed
- Never stop or change either medication without first consulting your healthcare provider