Colesevelam and Norethindrone Interaction
Drug interaction information between Colesevelam and Norethindrone.
Colesevelam and Norethindrone have a documented minor interaction in FDA labeling.
FDA drug labeling documents a minor-severity interaction between Colesevelam and Norethindrone. 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
Colesevelam can reduce the amount of birth control medicine that enters your body. This happens because the drug can trap the birth control in your digestive system before it can work.
What To Do
Talk to your doctor about the best timing for taking these medications to ensure your birth control stays effective. You may need to take them several hours apart.
FDA Label Information
7 DRUG INTERACTIONS Concomitant use with colesevelam hydrochloride may decrease the exposure of the following drugs: Drugs with a narrow therapeutic index (e.g., cyclosporine), phenytoin, thyroid hormone replacement therapy, warfarin, oral contraceptives containing ethinyl estradiol and norethindrone, olmesartan medoxomil, and sulfonylureas (glimepiride, glipizide, glyburide). Oral Contraceptives Containing Ethinyl Estradiol and Norethindrone Clinical Impact: In vivo drug interactions studies showed a decrease in exposure of ethinyl estradiol and norethindrone when coadministered with...
Colesevelam Also Interacts With
- Olmesartan moderate
- Metformin minor
- Warfarin minor
- Cyclosporine minor
- Glyburide minor
Norethindrone Also Interacts With
- Voriconazole major
- Atorvastatin minor
- Colchicine minor
- Darunavir minor
- Fluconazole minor
Frequently Asked Questions
Can I take Colesevelam and Norethindrone together?
This is a minor interaction. Talk to your doctor about the best timing for taking these medications to ensure your birth control stays effective. You may need to take them several hours apart.
How serious is the interaction between Colesevelam and Norethindrone?
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 Colesevelam and Norethindrone interact?
Colesevelam can reduce the amount of birth control medicine that enters your body. This happens because the drug can trap the birth control in your digestive system before it can work.
Understanding the Colesevelam and Norethindrone Interaction
FDA-approved prescribing information for these two drugs flags their combination as a minor-severity interaction. Colesevelam belongs to the Bile Acid Sequestrant (Diabetes) class and Norethindrone belongs to the Progestin-Only Oral Contraceptive class - two categories that can collide when co-prescribed. The mechanism described in FDA labeling is: Colesevelam can reduce the amount of birth control medicine that enters your body. 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. Colesevelam has 15 total documented interactions on file in this dataset, and Norethindrone has 10. 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: Talk to your doctor about the best timing for taking these medications to ensure your birth control stays effective. 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 Colesevelam or Norethindrone 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.