Drug interactions
Rifapentine + Warfarin
Severity: Major
Rifapentine and Warfarin: major interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Rifapentine is an inducer of hepatic enzymes and may markedly increase warfarin clearance. INR can fall considerably, and recurrent thromboembolism may occur if doses are not adjusted.
What this interaction means in plain words
Rifapentine and Warfarin can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for.
Rifapentine belongs to Anti Bacterial; Warfarin belongs to Cardiovascular.
Why it happens
Induction of CYP2C9 and CYP3A4 by rifapentine increases warfarin metabolism.
What to do
Monitor INR frequently during rifapentine therapy and increase warfarin dose as needed. Recheck INR after rifapentine is stopped as induction wanes.
What to ask your pharmacist
- Does the benefit of taking both outweigh the risk in my case?
- Do I need any blood test, ECG or other check while on both?
- What early warning signs should I watch for, and what should I do if they appear?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Rifapentine and Warfarin, the additional notes, the evidence detail and the whole-prescription interaction checker.
- Full clinical management advice
- Additional notes
- Evidence detail
- Interaction checker for a whole prescription
Try Pro+ free for 14 days on the web. No card needed.
Other interactions of Warfarin
- Defibrotide + Warfarin Contraindicated
- Ketorolac + Warfarin Contraindicated
- Abciximab + Warfarin Major
- Acetylsalicylic acid + Warfarin Major
- Adagrasib + Warfarin Major
- Amiodarone + Warfarin Major
Other interactions of Rifapentine
- Ledipasvir-sofosbuvir + Rifapentine Contraindicated
- Lorlatinib + Rifapentine Contraindicated
- Lurasidone + Rifapentine Contraindicated
- Ranolazine + Rifapentine Contraindicated
- Rifapentine + Sofosbuvir-velpatasvir Contraindicated
- Rifapentine + Sofosbuvir-velpatasvir-voxilaprevir Contraindicated
Frequently asked questions
Can I take Rifapentine with Warfarin?
MediHelp rates the interaction as major. Rifapentine and Warfarin can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for. Rifapentine is an inducer of hepatic enzymes and may markedly increase warfarin clearance. INR can fall considerably, and recurrent thromboembolism may occur if doses are not adjusted.
How serious is the interaction between Rifapentine and Warfarin?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor INR frequently during rifapentine therapy and increase warfarin dose as needed. Recheck INR after rifapentine is stopped as induction wanes.
What other medicines interact with Warfarin?
MediHelp also lists interactions of Warfarin with, for example, Defibrotide, Ketorolac, Abciximab. The full list is on the Warfarin page.
Full monographs, dosing and an interaction checker in the MediHelp app
Open the complete reference, check multi-drug interactions and use dosing tools in the MediHelp app.
