What is the dosing for paxlovid?

How often is Paxlovid taken each day?
Paxlovid comes as a co-packaged regimen of nirmatrelvir tablets and ritonavir tablets. The standard adult dose is two 150 mg nirmatrelvir tablets plus one 100 mg ritonavir tablet taken together twice daily for five days. The tablets should be swallowed whole with or without food and started as soon as possible after a positive COVID-19 test or within five days of symptom onset.

What happens if a dose is missed?
If a dose is missed and it has been less than eight hours since the scheduled time, take it right away and resume the regular schedule. If more than eight hours have passed, skip the missed dose and take the next dose at its usual time. Do not double the next dose.

Can the dose be adjusted for kidney or liver problems?
For patients with moderate kidney impairment (eGFR 30–60 mL/min), the dose is reduced to one 150 mg nirmatrelvir tablet plus one 100 mg ritonavir tablet taken twice daily. Paxlovid is not recommended for patients with severe kidney impairment (eGFR below 30 mL/min) or severe liver impairment (Child-Pugh Class C). No adjustment is needed for mild to moderate liver disease.

How does Paxlovid interact with other medicines?
Ritonavir strongly inhibits CYP3A and may raise levels of many common drugs, including certain statins, antiarrhythmics, sedatives, and blood thinners. Clinicians review a patient’s full medication list before prescribing and may temporarily hold or switch interacting drugs. Patients should not start or stop any medicine without checking with their prescriber or pharmacist.

When does Paxlovid’s exclusivity end?
The FDA originally granted Paxlovid emergency-use authorization in December 2021. Pfizer’s composition-of-matter patents covering nirmatrelvir are listed to expire in 2041 on DrugPatentWatch.com, but regulatory exclusivities tied to the EUA and subsequent full approval may end earlier and allow generic entry sooner.