Does Phenobarbital Interact with Quinidine Sulfate Tablet?
CDI records a moderate classification for Phenobarbital and Quinidine Sulfate Tablet. The stored summary is: Induces cytochrome P450 IIIA4, accelerating hepatic elimination and decreasing quinidine levels. The mechanism involves induction of cytochrome p450 iiia4. 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
- Management
- Monitor for effects
- Data Source
- U.S. FDA via OpenFDA
Recorded Mechanism
Induction of cytochrome P450 IIIA4
What To Tell Your Doctor or Pharmacist
If you are taking Phenobarbital and your doctor is considering prescribing Quinidine Sulfate Tablet (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