Paxlovid is the brand name for nirmatrelvir co-packaged with ritonavir. Nirmatrelvir inhibits the SARS-CoV-2 main protease (3CLpro/Mpro), blocking viral replication. Ritonavir is added as a pharmacokinetic booster (CYP3A inhibitor) to increase nirmatrelvir plasma concentrations. Used for mild-to-moderate COVID-19 in high-risk adults.

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How to Pronounce Nirmatrelvir (Paxlovid)

nir-MA-trel-vir

IPA: /nɪr.ˈmæ.trɛl.vɪr/

Brand name: Paxlovid (with ritonavir)

nir MA trel vir

How do you pronounce Nirmatrelvir?

Nirmatrelvir is pronounced “nir-MA-trel-vir”. It has 4 syllables: nir – ma – trel – vir. The stress falls on the second syllable, “MA”. The brand name Paxlovid combines nirmatrelvir (pink tablets) with ritonavir (white tablet) as a pharmacokinetic booster.

How many syllables are in Nirmatrelvir?

Nirmatrelvir has 4 syllables: nir – ma – trel – vir.

What does Nirmatrelvir mean?

Nirmatrelvir is a peptidomimetic covalent inhibitor of the SARS-CoV-2 main protease (Mpro, also called 3CLpro). By blocking Mpro, it prevents cleavage of the viral polyprotein into functional non-structural proteins required for viral replication. Ritonavir is co-packaged not as an antiviral but as a CYP3A inhibitor that slows nirmatrelvir metabolism, maintaining therapeutic plasma levels. The combination reduces hospitalization and death risk by ~89% in high-risk unvaccinated patients when started within 5 days of symptom onset.

Word Parts

nirma- unique drug stem

-trelvir protease inhibitor antiviral suffix

Common Mispronunciations

Often mispronounced “nir-mat-REL-vir” (stress on third syllable) — correct stress is on the second: nir-MA-trel-vir. Also commonly called “Paxlovid” in clinical settings; “nirmatrelvir” is the generic component name.

Where You’ll Encounter This

Nirmatrelvir/ritonavir (Paxlovid) is prescribed in primary care, urgent care, and emergency settings for mild-to-moderate COVID-19 in adults at high risk of progression. Significant drug interactions occur due to ritonavir CYP3A inhibition (statins, immunosuppressants, anticoagulants). Requires renal dose adjustment; contraindicated with eGFR <30. Treatment is 5 days, started as early as possible after diagnosis.