Key takeaways:
Paxlovid (nirmatrelvir / ritonavir) is an oral antiviral medication that’s FDA approved to treat people at high risk of developing severe illness from COVID-19. Adults and children ages 12 and older with mild-to-moderate COVID who weigh at least 88 lbs (40 kg) are eligible to take it.
The typical Paxlovid dosage is 2 tablets (300 mg) of nirmatrelvir and 1 tablet (100 mg) of ritonavir by mouth twice a day for 5 days. It’s recommended to take your Paxlovid doses 12 hours apart.
Paxlovid isn’t recommended for people with severe kidney or liver problems. If you have moderate kidney problems, you’ll only take 1 nirmatrelvir tablet per dose instead of 2 tablets.
Save on related medications
Paxlovid (nirmatrelvir / ritonavir) has been a game changer for treating COVID-19. It’s FDA approved to treat people at high risk of developing severe illness from the virus, and it’s now widely available at pharmacies across the U.S.
It’s also considered an effective, first-choice treatment option. In early studies, Paxlovid reduced the likelihood of COVID-related hospitalization or death by about 90%. And more recent studies also show that Paxlovid lowers the risk of hospitalization against newer viral variants.
Paxlovid is a combination of two different antiviral medications: nirmatrelvir and ritonavir. It comes in a prepackaged box that contains a 5-day course of medication. If you have mild-to-moderate COVID, you may be eligible to receive Paxlovid. A healthcare professional will perform checks to make sure you can take Paxlovid safely and at the right dosage.
Search and compare options
What’s the typical Paxlovid dosage for adults?
The recommended Paxlovid dosage for adults is 2 tablets (300 mg) of nirmatrelvir and 1 tablet (100 mg) of ritonavir every 12 hours for 5 days. You should swallow these 3 tablets at the same time with every dose. That’s a total of 6 tablets per day — or 30 tablets for the entire 5-day course.
To be most effective, you should start taking Paxlovid within 5 days of your first symptoms or testing positive for COVID. You can take it with or without food, but make sure to swallow the tablets whole. Don’t crush, chew, or split them.
What’s the typical Paxlovid dosage for children?
Paxlovid is technically only approved for adults. But it’s still authorized in children and teens ages 12 and older who weigh at least 88 lbs (40 kg). Children who meet these age and body weight requirements, and are at high risk for severe illness, receive the same dose as adults.
The standard Paxlovid dosage for kids who meet this criteria is 2 tablets (300 mg) of nirmatrelvir and 1 tablet (100 mg) of ritonavir every 12 hours for 5 days.
Are there any dosage adjustments for medical conditions?
Some people aren’t able to take the standard dose of Paxlovid due to certain health conditions or drug interactions. Before you start taking Paxlovid, your prescriber should ask you about your health history and for a complete list of medications and supplements you take. If necessary, they can adjust your Paxlovid dosing based on these factors.
Dosage for people with kidney (renal) problems
You may need to take a lower dose of Paxlovid if you have kidney impairment.
For mild kidney problems, no dosage adjustment is necessary. For severe kidney problems, Paxlovid isn’t recommended at all. The middle ground is where adjustments are needed.
If you have moderate kidney problems, you’ll take a lower dose of Paxlovid. The Paxlovid dosage for people with moderate kidney problems is 1 tablet (150 mg) of nirmatrelvir and 1 tablet (100 mg) of ritonavir every 12 hours for 5 days. That’s 1 less tablet per dose.
Paxlovid is supplied in two different packages: Standard Dose and Reduced Dose. If it’s in stock, your pharmacist will give you the Reduced Dose pack. This package contains 20 tablets instead of 30. If it’s not in stock, your pharmacist will give you the Standard Dose pack, but they’ll manually remove the extra nirmatrelvir tablets.
What it feels like: Three people share their experiences with Paxlovid, which can be beneficial for people at high risk from COVID.
How to get the medication: There are several ways to fill a Paxlovid prescription at the pharmacy if you qualify for the treatment.
Interactions with other drugs: Paxlovid interacts with hundreds of other medications. But many interactions can be managed with dosage adjustments.
Other COVID treatments: In addition to Paxlovid, read about what other options are available for treating and preventing COVID.
Dosage for people with liver problems
If you have mild or moderate liver problems, you can take the standard Paxlovid dosage. But if your liver problems are more severe, you shouldn’t take Paxlovid.
This is partly due to the ritonavir portion of Paxlovid. In past studies, ritonavir has contributed to issues like jaundice and changes in liver protein levels. There’s also limited data on how Paxlovid itself affects the liver.
Paxlovid drug interaction considerations
Paxlovid interacts with many medications and supplements. Some interactions make Paxlovid less effective, while others make it overly abundant. Having too much Paxlovid in the body can worsen its side effects. Paxlovid can also impact the effectiveness and tolerability of other medications.
Some Paxlovid interactions include:
Blood thinners like rivaroxaban (Xarelto)
Cholesterol medications like simvastatin (Zocor, FloLipid)
Heart medications like amiodarone (Pacerone)
Anti-seizure medications like carbamazepine (Tegretol)
Erectile dysfunction medications like tadalafil (Cialis, Adcirca, Alyq, Tadliq)
St. John’s wort, a dietary supplement
Depending on the interaction, your healthcare professional may need to adjust your Paxlovid dosage. They could also adjust the dosage of the other medication that’s causing a conflict.
You should avoid other interactions altogether. In some cases, you may be asked to temporarily stop taking a medication that interacts with Paxlovid. If this isn’t possible, you may be prescribed a different COVID treatment with fewer interactions, such as Lagevrio (molnupiravir) or Veklury (remdesivir).
What happens if you miss a dose of Paxlovid?
Everyone is forgetful at some point. People make mistakes. So if you forget to take a dose of Paxlovid, don’t worry. There are some built-in directions to follow if this situation pops up.
If you miss a dose of Paxlovid and it’s within 8 hours of when you were supposed to take it, take your missed dose as soon as possible. Continue with your normal Paxlovid dosing schedule after that.
If more than 8 hours have passed since your missed dose, skip the missed dose altogether. Take your next dose at your normal time. Don’t take an extra dose to make up for the missed one, either — this raises the risk of side effects like diarrhea and liver problems.
What should you do if you take too much Paxlovid?
If you take too much Paxlovid, call a healthcare professional as soon as you can. There’s no specific antidote for a Paxlovid overdose, so they can evaluate your situation and recommend treatments for side effects that may pop up. Contacting Poison Control online or at 1-800-222-1222 is another option.
If you feel like you’re having serious or life-threatening symptoms, it’s better to call 911 or go to the nearest ER right away.
Test your knowledge about Paxlovid
Frequently asked questions
Paxlovid starts working quickly. Its effects aren’t immediately noticeable though. You might feel some improvement in your symptoms within 1 to 2 days, while full relief could take up to 4 days. In some cases, certain symptoms may linger past this time frame.
Yes, you can take your first dose of Paxlovid in the evening. You’ll then take your second dose the following morning. This won’t make a difference in how well the medication works. At the end of your Paxlovid course, your last dose will just be in the morning instead of the evening.
Yes, Paxlovid may occasionally cause side effects. Most of them are short lived. Taste changes and diarrhea are the most common. Side effects such as headaches, nausea, and stomach pain have been reported in some cases too. Reach out to a healthcare professional without delay if you notice any problematic or lingering side effects after starting Paxlovid.
Paxlovid starts working quickly. Its effects aren’t immediately noticeable though. You might feel some improvement in your symptoms within 1 to 2 days, while full relief could take up to 4 days. In some cases, certain symptoms may linger past this time frame.
Yes, you can take your first dose of Paxlovid in the evening. You’ll then take your second dose the following morning. This won’t make a difference in how well the medication works. At the end of your Paxlovid course, your last dose will just be in the morning instead of the evening.
Yes, Paxlovid may occasionally cause side effects. Most of them are short lived. Taste changes and diarrhea are the most common. Side effects such as headaches, nausea, and stomach pain have been reported in some cases too. Reach out to a healthcare professional without delay if you notice any problematic or lingering side effects after starting Paxlovid.
The bottom line
The standard Paxlovid dosage is 2 tablets (300 mg) of nirmatrelvir and 1 tablet (100 mg) of ritonavir every 12 hours for 5 days. If you have moderate kidney problems, you’ll take 1 less nirmatrelvir tablet with every dose. Certain people should avoid taking Paxlovid altogether. Paxlovid isn’t recommended in kids younger than 12 years old or in people with severe kidney or liver problems. Certain drug interactions can also get in the way and affect Paxlovid dosing.
Why trust our experts?
References
Bhimraj, A., et al. (2025). IDSA guidelines on the treatment and management of patients with COVID-19. Clinical Infectious Diseases.
MedlinePlus. (2023). Nirmatrelvir and ritonavir.
Pfizer. (n.d.). Paxlovid dosing and administration.
Pfizer. (2021). Pfizer’s novel COVID-19 oral antiviral treatment candidate reduced risk of hospitalization or death by 89% in interim analysis of phase 2/3 EPIC-HR study.
Pfizer Laboratories Division, Pfizer. (2025). Paxlovid - nirmatrelvir and ritonavir [package insert].
U.S. Food and Drug Administration. (n.d.). Fact sheet for healthcare providers: Emergency use authorization for Paxlovid.
U.S. Food and Drug Administration. (n.d.). Important Paxlovid eua dispensing information for patients with moderate renal impairment.
U.S. Food and Drug Administration. (2023). FDA approves first oral antiviral for treatment of COVID-19 in adults.
