Drug interactions
Nirmatrelvir + Sirolimus
Severity: Major
Nirmatrelvir and Sirolimus: 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
Nirmatrelvir is a CYP3A4 inhibitor and, particularly when boosted, can sharply increase sirolimus exposure. Toxicity may be severe given sirolimus's narrow therapeutic window.
What this interaction means in plain words
Nirmatrelvir and Sirolimus 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.
Nirmatrelvir belongs to Anti Virals; Sirolimus belongs to Miscellaneous.
Why it happens
Inhibition of CYP3A4 mediated sirolimus metabolism.
What to do
Avoid the combination where possible and consider an alternative COVID-19 antiviral. If used, hold or markedly reduce sirolimus and monitor trough levels.
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 Sirolimus
- Adenovirus types 4 and 7 live + Sirolimus Contraindicated
- Bcg vaccine live + Sirolimus Contraindicated
- Influenza virus vaccine quadrivalent intranasal + Sirolimus Contraindicated
- Ketoconazole + Sirolimus Contraindicated
- Levoketoconazole + Sirolimus Contraindicated
- Measles mumps and rubella vaccine live + Sirolimus Contraindicated
Other interactions of Nirmatrelvir
- Alfuzosin + Nirmatrelvir Contraindicated
- Amiodarone + Nirmatrelvir Contraindicated
- Apalutamide + Nirmatrelvir Contraindicated
- Carbamazepine + Nirmatrelvir Contraindicated
- Colchicine + Nirmatrelvir Contraindicated
- Dronedarone + Nirmatrelvir Contraindicated
Frequently asked questions
Can I take Nirmatrelvir with Sirolimus?
MediHelp rates the interaction as major. Nirmatrelvir and Sirolimus 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. Nirmatrelvir is a CYP3A4 inhibitor and, particularly when boosted, can sharply increase sirolimus exposure. Toxicity may be severe given sirolimus's narrow therapeutic window.
How serious is the interaction between Nirmatrelvir and Sirolimus?
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 the combination where possible and consider an alternative COVID-19 antiviral. If used, hold or markedly reduce sirolimus and monitor trough levels.
What other medicines interact with Sirolimus?
MediHelp also lists interactions of Sirolimus with, for example, Adenovirus types 4 and 7 live, Bcg vaccine live, Influenza virus vaccine quadrivalent intranasal. The full list is on the Sirolimus page.
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