Does Phenytoin Interact with Levoleucovorin?
CDI records a moderate classification for Phenytoin and Levoleucovorin. The stored summary is: Folic acid in large amounts may counteract antiepileptic effect and increase seizure frequency in susceptible children. Monitor patients taking levoleucovorin with this drug. The mechanism involves folic acid counteracts antiepileptic effect through shared metabolic pathways. Patients taking both medications should consult their healthcare provider before starting, stopping, or changing the dosage of either drug. This record was extracted from drug labeling through openFDA. NIH/NLM RxNorm is used for drug identities. The summary and severity classification are CDI's processed information, not a verbatim source quotation. Product, route, and patient circumstances matter.
- Severity
- Moderate
- Phenytoin Class
- Anti-epileptic Agent
- Management
- Monitor for effects
- Data Source
- U.S. FDA via OpenFDA
Recorded Mechanism
Folic acid counteracts antiepileptic effect through shared metabolic pathways
What To Tell Your Doctor or Pharmacist
If you are taking Phenytoin and your doctor is considering prescribing Levoleucovorin (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