Phenobarbital and Canagliflozin Interaction
Drug interaction information between Phenobarbital and Canagliflozin.
Phenobarbital and Canagliflozin have a documented moderate interaction in FDA labeling.
FDA drug labeling documents a moderate-severity interaction between Phenobarbital and Canagliflozin. Major interactions are generally avoided, moderate ones may need monitoring or a dose adjustment, and minor ones are usually low-risk. This page shows the documented mechanism and guidance. Label-documented interactions are not a complete safety review, so always confirm your own medications with a pharmacist or doctor. Educational information, not medical advice.
How They Interact
Phenobarbital speeds up the breakdown of canagliflozin in your body, which can make the diabetes medicine less effective.
What To Do
Monitor your blood sugar levels regularly and consult your doctor about potential dosage changes.
FDA Label Information
Examples: Rifampin, phenytoin, phenobarbital, ritonavir Insulin or Insulin Secretagogues Clinical Impact: The risk of hypoglycemia is increased when INVOKANA is used concomitantly with insulin secretagogues (e.g., sulfonylurea) or insulin.
Phenobarbital Also Interacts With
- Nirmatrelvir/Ritonavir major
- Ranolazine major
- Voriconazole major
- Cenobamate moderate
- Clarithromycin moderate
Canagliflozin Also Interacts With
View all Canagliflozin interactions →Frequently Asked Questions
Can I take Phenobarbital and Canagliflozin together?
This is a moderate interaction. Monitor your blood sugar levels regularly and consult your doctor about potential dosage changes.
How serious is the interaction between Phenobarbital and Canagliflozin?
This interaction is classified as "moderate" severity by the FDA. Moderate interactions may worsen your condition or change how your medications work.
Why do Phenobarbital and Canagliflozin interact?
Phenobarbital speeds up the breakdown of canagliflozin in your body, which can make the diabetes medicine less effective.
Understanding the Phenobarbital and Canagliflozin Interaction
FDA-approved prescribing information for these two drugs flags their combination as a moderate-severity interaction. Phenobarbital belongs to the Anticonvulsant (Barbiturate) class and Canagliflozin belongs to the SGLT2 Inhibitor class - two categories that can collide when co-prescribed. The mechanism described in FDA labeling is: Phenobarbital speeds up the breakdown of canagliflozin in your body, which can make the diabetes medicine less effective. Severity tiers matter: major flags generally advise avoidance, moderate flags often require monitoring or dose adjustment, and minor flags may only call for awareness.
Context around a specific patient determines real-world impact. Phenobarbital has 59 total documented interactions on file in this dataset, and Canagliflozin has 5. Each additional medication compounds the interaction surface, which is why pharmacists run full-profile checks rather than evaluating one pair at a time. FDA-derived guidance for this pair is: Monitor your blood sugar levels regularly and consult your doctor about potential dosage changes. Timing of doses, renal and hepatic function, age, and other concurrent prescriptions all shape whether a labeled interaction matters clinically.
An interaction flag is not a verdict. A large share of labeled interactions are managed routinely in clinical practice, the fix may be as simple as spacing doses or adding a monitoring test. Others require the prescriber to choose a different medication entirely. This page surfaces FDA-sourced labeling and openFDA data for educational purposes only; it is not medical advice and cannot account for your full clinical picture. Never start, stop, or adjust either Phenobarbital or Canagliflozin based on a web page, speak with your prescriber or pharmacist before making any change.
Sources: FDA Drug Labels (SPL) via openFDA (2026). This is for informational purposes only and is not medical advice. Always consult your healthcare provider about drug interactions.
Read our methodology - how this data is sourced, computed, and verified.