Paxlovid for Covid-19: The Basics

Jake Bissaro
Jake Bissaro
Jun 6
A man in a white t-shirt is looking out the window while holding a pill with his left hand and drinking a glass of water with his right

Though case counts and hospitalization rates have subsided, Covid-19 is still very much with us—even after these grueling last two years. The good news is that the FDA has issued emergency use authorization for several at-home antiviral treatments, including Paxlovid, which has proven to be very effective at preventing hospitalization or death in high-risk patients.

Dr. B started as a Covid-19 vaccine standby list and was able to offer patients over one million vaccines. We’re now advancing our mission in a new way by offering prescription consultations for Paxlovid–the first of many everyday prescriptions available as part of our new online health service.

Curious whether you’re eligible for Paxlovid? Want to know more about what to expect from the treatment? We’ve got answers below. 

What is Paxlovid?

Paxlovid is an oral antiviral treatment manufactured by Pfizer that has proven effective at reducing the chances of hospitalization or death among high-risk patients who have Covid-19. Paxlovid—the drug’s brand name—comprises the generic medications Nirmatrelvir and Ritonavir.

The at-home treatment essentially works by disrupting the life cycle of the Covid-19 virus. Nirmatrelvir prevents the virus proteins from replicating while Ritonavir (a “pharmacokinetic booster”) slows Nirmatrelvir’s rate of metabolization in the liver, boosting its efficacy and giving it more time to fight off the infection. 

It’s important to note that Paxlovid is not a substitute for a Covid-19 vaccination—if you haven’t been vaccinated and boosted, it’s recommended that you do so as soon as possible.

How effective is Paxlovid?

Though Paxlovid isn’t the only treatment on the market for Covid-19, it’s currently the most effective by a significant margin. Paxlovid was granted emergency use authorization by the U.S. Food and Drug Administration (FDA) in December of 2021 based on clinical trial data that showed an 89% reduction in the risk of hospitalization or death among high-risk adults. 

Though pediatric patients weren’t included in the initial trial, the FDA has approved the use of Paxlovid in high-risk patients who are 12 and up and weigh at least 88 pounds.

In April, the World Health Organization (WHO) made a strong recommendation in favor of Paxlovid distribution, and the treatment is a foundation of the White House’s new Test to Treat program. The European Medicines Agency (EMA) has also authorized the treatment for use across the European Union. 

How is Paxlovid taken?

Paxlovid is prescribed as a three-pill dose—two pills of Nirmatrelvir and one of Ritonavir—to be taken twice a day, 12 hours apart, for five days. All three pills should be taken together with plenty of water, and never chewed or crushed. You should finish taking the full course of Paxlovid, even if your symptoms begin to improve. 

The treatment window for Paxlovid is relatively short. It must be taken within five days of the start of symptoms (and ideally as soon as possible). If you’re experiencing what you believe to be Covid-19 symptoms, but get a negative result on a rapid test, it’s recommended that you take a PCR test or continue to test at home. 

What are the side effects of Paxlovid?

Paxlovid patients commonly experience the following side effects:

  • Diarrhea
  • Impaired sense of taste 
  • Increased blood pressure
  • Muscle aches

The good news is these side effects are generally mild. 

In some cases, Paxlovid can cause an allergic reaction. If you experience symptoms like hives; trouble breathing; swelling of the mouth, lips or face; or skin rash, stop taking the medication and call your doctor immediately. 

Paxlovid does have negative interactions with a range of drugs, including anticancer, antifungal and statin medications. You can see our Paxlovid page for a full list of drug interactions.

According to recent reports, in roughly 1-2% of Covid-19 cases, Paxlovid patients are experiencing a resurgence of Covid-19 symptoms—and in some cases even testing positive again following their initial bout with the virus. Despite this “rebound” phenomenon, experts still say Paxlovid is the most effective tool for preventing Covid-19 hospitalization and there is no evidence that rebound symptoms require additional treatment. 

Who is eligible for Paxlovid? 

At this time, Paxlovid isn’t available to the general population. The treatment is intended for people with mild or moderate cases of Covid-19 who are at high risk of becoming seriously ill. 

To be prescribed the treatment, you must have a positive Covid-19 test result (either PCR or at-home antigen test), have experienced symptoms for five days or less, and fall into one of two categories:

  • Be 65 years or older
  • Have certain medical conditions, including:
    • Cancer
    • Chronic kidney disease
    • Chronic lung diseases
    • Cystic fibrosis
    • Dementia
    • Diabetes
    • Disabilities such as cerebral palsy and spinal cord injuries
    • Heart conditions
    • Mental health conditions
    • Obesity
    • Sickle cell disease
    • Substance use disorders

View the full list of medical conditions at the CDC website

Paxlovid is available to people 12 and older who weigh at least 88 pounds. 

The treatment is only effective if started within the first five days of symptoms. After you have tested positive, don’t delay in getting a Paxlovid prescription if eligible. 

How can I access Paxlovid?

If you have tested positive, there are multiple ways to access Paxlovid, now widely available throughout the U.S. 

You can access the treatment through:

  • Dr. B: Dr. B is currently offering online prescription consultations for Paxlovid and Molnupiravir. After completing an online health assessment, a board-certified doctor will review your responses and, if treatment is appropriate, send a prescription to your pharmacy of choice. 
  • Your doctor: If you have a primary care provider, ask them about Paxlovid as soon as possible. 
  • Federal and state programs: Check which programs are available in your area. For example, the Biden administration purchased 20 million treatment courses of Paxlovid at the end of April to be made available for free through the Test to Treat program

To learn more about the Dr. B platform, check out our FAQ page or shoot us an email at hi@hidrb.com.

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