Nirmatrelvir and ritonavir and Sirolimus interaction
Nirmatrelvir and ritonavir and Sirolimus: both prescribing labels flag this combination with the strongest language, such as a contraindication, a boxed warning, or an instruction to avoid it.
Do not combine without a prescriber's guidance. The label language below is the strongest FDA uses.
What the FDA labels say
From the Nirmatrelvir and ritonavir (Paxlovid) label · effective 2026-02-19
Obtain expert consultation to appropriately manage the complexity of this co-administration [see Warnings and Precautions (5.1) ] . mTOR inhibitors: everolimus, sirolimus ↑ everolimus ↑ sirolimus Avoid concomitant use of everolimus and sirolimus and PAXLOVID.
…methylergonovine • HMG-CoA reductase inhibitors: lovastatin, simvastatin (these drugs can be temporarily discontinued to allow PAXLOVID use [see Table 2 , Drug Interactions (7.3) ] ) • Immunosuppressants: voclosporin • Microsomal triglyceride transfer protein inhibitor: lomitapide • Migraine medications: eletriptan, ubrogepant • Mineralocorticoid receptor antagonists:…
Immunosuppressants voclosporin ↑ voclosporin Co-administration contraindicated due to potential for acute and/or chronic nephrotoxicity [see Contraindications (4) ] .
Immunosuppressants calcineurin inhibitors: cyclosporine, tacrolimus ↑ cyclosporine ↑ tacrolimus Avoid concomitant use of calcineurin inhibitors with PAXLOVID when close monitoring of immunosuppressant concentrations is not feasible.
If co-administered, dose adjustment of the immunosuppressant and close and regular monitoring for immunosuppressant concentrations and adverse reactions are recommended during and after treatment with PAXLOVID.
From the Sirolimus label · effective 2026-03-26
Interaction with Strong Inhibitors and Inducers of CYP3A4 and/or P-gp Avoid concomitant use of sirolimus with strong inhibitors of CYP3A4 and/or P-gp (such as ketoconazole, voriconazole, itraconazole, erythromycin, telithromycin, or clarithromycin) or strong inducers of CYP3A4 and/or P-gp (such as rifampin or rifabutin) [ see Drug Interactions (7.2) ].
• Avoid concomitant use with strong CYP3A4/P-gp inducers or strong CYP3A4/P-gp inhibitors that decrease or increase sirolimus concentrations ( 7.4 , 12.3 ).
Strong Inducers and Strong Inhibitors of CYP3A4 and P-gp Avoid concomitant use of sirolimus with strong inducers (e.g., rifampin, rifabutin) and strong inhibitors (e.g., ketoconazole, voriconazole, itraconazole, erythromycin, telithromycin, clarithromycin) of CYP3A4 and P-gp.
…concentrations: Bromocriptine, cimetidine, cisapride, clotrimazole, danazol, diltiazem, fluconazole, letermovir, protease inhibitors (e.g., HIV and hepatitis C that include drugs such as ritonavir, indinavir, boceprevir, and telaprevir), metoclopramide, nicardipine, troleandomycin, verapamil • Drugs and other agents that could decrease sirolimus concentrations: Carbamazepine,…
Inducers of CYP3A4 and P-gp may decrease sirolimus concentrations whereas inhibitors of CYP3A4 and P-gp may increase sirolimus concentrations.
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Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.