Drug interactions
Leflunomide + Yellow fever vaccine
Severity: Major
Leflunomide and Yellow fever vaccine: 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
Yellow fever vaccine is live attenuated and carries a risk of vaccine-associated viscerotropic or neurotropic disease in immunosuppressed patients. Leflunomide may also reduce protective immunity.
What this interaction means in plain words
Leflunomide and Yellow fever vaccine 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.
Why it happens
Immunosuppression through dihydroorotate dehydrogenase inhibition allows increased replication of the live vaccine virus.
What to do
Avoid vaccination during therapy and avoid travel to endemic areas if possible. If travel is essential, give a medical exemption letter or seek specialist advice about drug washout before vaccination.
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?
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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
Frequently asked questions
Can I take Leflunomide with Yellow fever vaccine?
MediHelp rates the interaction as major. Leflunomide and Yellow fever vaccine 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. Yellow fever vaccine is live attenuated and carries a risk of vaccine-associated viscerotropic or neurotropic disease in immunosuppressed patients. Leflunomide may also reduce protective immunity.
How serious is the interaction between Leflunomide and Yellow fever vaccine?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid vaccination during therapy and avoid travel to endemic areas if possible. If travel is essential, give a medical exemption letter or seek specialist advice about drug washout before vaccination.
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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