Drug interactions
Leflunomide + Warfarin
Severity: Moderate
Leflunomide and Warfarin: moderate 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
Leflunomide may raise the INR in patients taking warfarin, and bleeding has been reported in this setting. Teriflunomide may also inhibit CYP2C9 modestly, but the effect on warfarin is inconsistent.
What this interaction means in plain words
Leflunomide and Warfarin can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Leflunomide belongs to Musculoskeletal; Warfarin belongs to Cardiovascular.
Why it happens
Possible inhibition of CYP2C9-mediated warfarin metabolism by teriflunomide; the mechanism is not firmly established.
What to do
Check INR more often when starting or stopping leflunomide and adjust the warfarin dose as needed. Counsel the patient to report any bleeding.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
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Other interactions of Leflunomide
- Bcg vaccine live + Leflunomide Contraindicated
- Influenza virus vaccine quadrivalent intranasal + Leflunomide Contraindicated
- Leflunomide + Measles mumps and rubella vaccine live Contraindicated
- Leflunomide + Measles mumps rubella and varicella vaccine live Contraindicated
- Leflunomide + Measles vaccine Contraindicated
- Leflunomide + Smallpox vaccine live Contraindicated
Other interactions of Warfarin
- Defibrotide + Warfarin Contraindicated
- Ketorolac + Warfarin Contraindicated
- Abciximab + Warfarin Major
- Acetylsalicylic acid + Warfarin Major
- Adagrasib + Warfarin Major
- Amiodarone + Warfarin Major
Frequently asked questions
Can I take Leflunomide with Warfarin?
MediHelp rates the interaction as moderate. Leflunomide and Warfarin can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Leflunomide may raise the INR in patients taking warfarin, and bleeding has been reported in this setting. Teriflunomide may also inhibit CYP2C9 modestly, but the effect on warfarin is inconsistent.
How serious is the interaction between Leflunomide and Warfarin?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Check INR more often when starting or stopping leflunomide and adjust the warfarin dose as needed. Counsel the patient to report any bleeding.
What other medicines interact with Leflunomide?
MediHelp also lists interactions of Leflunomide with, for example, Bcg vaccine live, Influenza virus vaccine quadrivalent intranasal, Measles mumps and rubella vaccine live. The full list is on the Leflunomide page.
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