Trimethoprim and Glipizide Interaction
Drug interaction information between Trimethoprim and Glipizide.
Trimethoprim and Glipizide have a documented minor interaction in FDA labeling.
FDA drug labeling documents a minor-severity interaction between Trimethoprim and Glipizide. 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
Trimethoprim slows down how your body breaks down glipizide, which can make your blood sugar drop too low.
What To Do
You should monitor your blood sugar closely and watch for signs of it being too low, like feeling shaky or dizzy.
FDA Label Information
Sulfamethoxazole and trimethoprim potentiates the effect of oral hypoglycemics that are metabolized by CYP2C8 (e.g., pioglitazone, repaglinide, and rosiglitazone) or CYP2C9 (e.g., glipizide and glyburide) or eliminated renally via OCT2 (e.g., metformin).
Trimethoprim Also Interacts With
- Theophylline major
- Prenatal Multivitamin moderate
- Spironolactone moderate
- Spironolactone (Acne) moderate
- Metformin minor
Glipizide Also Interacts With
- Fluconazole minor
- Colesevelam minor
- Probenecid minor
- Phenytoin minor
- Lovastatin minor
Frequently Asked Questions
Can I take Trimethoprim and Glipizide together?
This is a minor interaction. You should monitor your blood sugar closely and watch for signs of it being too low, like feeling shaky or dizzy.
How serious is the interaction between Trimethoprim and Glipizide?
This interaction is classified as "minor" severity by the FDA. Minor interactions are unlikely to cause significant problems but should still be mentioned to your healthcare provider.
Why do Trimethoprim and Glipizide interact?
Trimethoprim slows down how your body breaks down glipizide, which can make your blood sugar drop too low.
Understanding the Trimethoprim and Glipizide Interaction
FDA-approved prescribing information for these two drugs flags their combination as a minor-severity interaction. Trimethoprim belongs to the Dihydrofolate Reductase Inhibitor class and Glipizide belongs to the Sulfonylurea class - two categories that can collide when co-prescribed. The mechanism described in FDA labeling is: Trimethoprim slows down how your body breaks down glipizide, which can make your blood sugar drop too low. 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. Trimethoprim has 22 total documented interactions on file in this dataset, and Glipizide has 8. 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: You should monitor your blood sugar closely and watch for signs of it being too low, like feeling shaky or dizzy. 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 Trimethoprim or Glipizide 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.