Does Choleystyramine Light Interact with Phenobarbital?
Choleystyramine Light and Phenobarbital have a moderate drug interaction according to U.S. FDA drug labeling data. Cholestyramine may delay or reduce absorption of phenobarbital. The mechanism involves binding and delayed/reduced 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
- Choleystyramine Light Class
- Bile Acid Sequestrant
- Management
- Monitor for effects
- Data Source
- U.S. FDA via OpenFDA
How This Interaction Works
The interaction between Choleystyramine Light and Phenobarbital occurs because binding and delayed/reduced absorption. Clinically, this means cholestyramine may delay or reduce absorption of phenobarbital. 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 Choleystyramine Light and your doctor is considering prescribing Phenobarbital (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