COVID-19 treatments Paxlovid: What you need to know

Credit: CC0 Public Domain

What is it? Paxlovid is Pfizer’s brand name for an antiviral oral medication (in pill form) that combines two generic drugs, nirmatrelvir and ritonavir.

It was the first COVID-19 antiviral pill to receive Food and Drug Administration (FDA) emergency use authorization (EUA), and the National Institutes of Health (NIH) has prioritized its use over other treatments for eligible patients. It is meant for people who have a current COVID-19 infection.

When it was authorized: December 2021.

Who can get it: People ages 12 and up who weigh at least 88 pounds, who have a positive COVID-19 test result, have symptoms, and are at high risk for developing severe COVID-19.

How you take it: For most people, the dose is three pills twice daily for five days, and it must be started within five days of developing COVID-19 symptoms.

Side effects: They’re usually mild, and may include altered or impaired sense of taste, diarrhea, increased blood pressure, or muscle aches. Because Paxlovid is still being studied, it’s possible that all of the risks aren’t yet known.

How it works: Paxlovid is an antiviral medication, a type of drug that stops viruses from replicating inside the body’s cells.

Two of the pills in the three-pill dose are nirmatrelvir, which prevents the SARS-CoV-2 virus from replicating.

The other medication is ritonavir, which gives the first drug’s levels a boost by essentially shutting down its metabolism in the liver, so that nirmatrelvir levels remain high and can work longer to fight the infection.

How well it works: 89% efficacy against hospitalization and death in the clinical trial, which included unvaccinated patients.

Though the trial was conducted before Omicron became the predominant variant, Pfizer says that the treatment appears to work well against it.

This is backed up by three laboratory-based studies (all of which involved Pfizer) that have not yet been published in peer-reviewed medical journals.

What else you should know: Paxlovid interacts with many medications, including common ones that are sold over the counter like St. John’s Wort, blood thinners, cholesterol medicines, and many more.

In some cases, this can cause complications that are serious enough to justify not taking it.

So, it’s important for doctors to have an up-to-date medication list, including over-the-counter medications and supplements; they may consider other treatments for some patients.

There is no experience treating pregnant women or breastfeeding mothers with Paxlovid. Women who are pregnant should discuss their options with their health care provider.

It is also recommended that patients use effective barrier contraception or do not have sexual activity while taking Paxlovid.

Paxlovid is also not recommended for patients with severe liver or kidney disease and those with HIV who are not on treatment.

If you care about COVID, please read studies about the key to curing COVID-19, and people with these mental problems less likely to get COVID-19.

For more information about COVID, please see recent studies about new antibody treatment for COVID-19, and results showing some inflammation drugs could help prevent COVID-19 deaths.