Ivacaftor and Nirmatrelvir and ritonavir interaction
Ivacaftor and Nirmatrelvir and ritonavir: 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
…delayed offset of the recently discontinued CYP3A inducer [see Drug Interactions (7.3) ] : • Anticancer drugs: apalutamide, enzalutamide • Anticonvulsant: carbamazepine, phenobarbital, primidone, phenytoin • Antimycobacterials: rifampin, rifapentine • Cystic fibrosis transmembrane conductance regulator potentiators: lumacaftor/ivacaftor • Herbal products: St.
Cystic fibrosis transmembrane conductance regulator potentiators lumacaftor/ivacaftor ↓ nirmatrelvir/ritonavir Co-administration contraindicated due to potential loss of virologic response and possible resistance [see Contraindications (4) ] .
Cystic fibrosis transmembrane conductance regulator potentiators ivacaftor elexacaftor/tezacaftor/ ivacaftor tezacaftor/ivacaftor ↑ ivacaftor ↑ elexacaftor/tezacaftor/ ivacaftor ↑ tezacaftor/ivacaftor Reduce dosage when co-administered with PAXLOVID.
From the Ivacaftor (Kalydeco) label · effective 2026-03-23
Potential for other drugs to affect ivacaftor CYP3A inhibitors: Reduce KALYDECO dosage in patients aged 6 months and older when co-administered with strong CYP3A inhibitors (e.g., ketoconazole) or moderate CYP3A inhibitors (e.g., fluconazole).
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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.