nirmatrelvir and ritonavir (Paxlovid)

Brand Names: Paxlovid

Generic Name: nirmatrelvir and ritonavir

What is nirmatrelvir and ritonavir (Paxlovid)?

Nirmatrelvir in combination with ritonavir is an experimental medicine being studied for the treatment of mild-to-moderate COVID-19. This drug is still being studied and all of its risks are not yet known.

The US Food and Drug Administration (FDA) has authorized emergency use of nirmatrelvir in combination with another medicine called ritonavir for the treatment of mild-to-moderate COVID-19 in adults and people 12 years of age and older (weighing at least 40 kg or 88 lbs) testing positive for COVID-19, and who are at high risk for progression to severe COVID-19, including hospitalization or death.

Nirmatrelvir and ritonavir is not authorized for use:

  • for initiation of treatment in people needing hospitalization due to COVID-19;
  • for prevention before or after exposure of COVID-19; or
  • longer than 5 consecutive days.

Nirmatrelvir and ritonavir may also be used for purposes not listed in this medication guide.

What are the possible side effects of nirmatrelvir and ritonavir (Paxlovid)?

Get emergency medical help if you have signs of an allergic reaction (hives, difficult breathing, swelling in your face or throat) or a severe skin reaction (fever, sore throat, burning eyes, skin pain, red or purple skin rash with blistering and peeling).

Call your doctor at once if you have:

Ritonavir affects your immune system, which may cause certain side effects (even weeks or months after you've taken this medicine). Tell your doctor if you have:

  • signs of a new infection--fever, night sweats, swollen glands, cold sores, cough, wheezing, diarrhea, weight loss;
  • trouble speaking or swallowing, problems with balance or eye movement, weakness or prickly feeling; or
  • swelling in your neck or throat (enlarged thyroid), menstrual changes, impotence.

Common side effects may include:

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What is the most important information I should know about nirmatrelvir and ritonavir (Paxlovid)?

The US Food and Drug Administration (FDA) has authorized emergency use of nirmatrelvir in combination with another medicine called ritonavir for the treatment of mild-to-moderate COVID-19 in adults and people 12 years of age and older (weighing at least 40 kg or 88 lbs).

What should I discuss with my healthcare provider before taking nirmatrelvir and ritonavir (Paxlovid)?

You should not use nirmatrelvir and ritonavir if you are allergic to it.

Some drugs should not be used with nirmatrelvir and ritonavir, such as those listed below.

Nirmatrelvir and ritonavir should not be started immediately after discontinuation of any of the following drugs:

Tell your doctor if:

COVID-19 is more likely to cause serious illness or death in a pregnant woman. Not all risks are known yet, but being treated with nirmatrelvir and ritonavir is likely to be less harmful than being infected with COVID-19 during pregnancy.

Ritonavir can make birth control pills or skin patches less effective. Ask your doctor about other birth control options such as an injection, implant, vaginal ring, condom, diaphragm, cervical cap, or contraceptive sponge.

How should I take nirmatrelvir and ritonavir (Paxlovid)?

Follow all directions on your prescription label and read all medication guides or instruction sheets. Use the medicine exactly as directed.

Take nirmatrelvir together with ritonavir (two tablets of nirmatrelvir and one tablet of ritonavir) twice a day for 5 consecutive days.

Take this medicine as soon as possible after diagnosis of COVID-19 and within 5 days of when symptoms first appear.

You may take nirmatrelvir and ritonavir with or without food.

Swallow the tablets whole and do not crush, chew, or break them.

You may need frequent blood tests to check your liver function.

Being treated with nirmatrelvir and ritonavir will not make you less contagious to other people. Keep using infection control methods such as self-isolation, social distancing, hand-washing, using protective face covering, disinfecting surfaces you touch a lot, and not sharing personal items with others.

Nirmatrelvir and ritonavir are still being studied and all of the risks are not yet known.

What happens if I miss a dose (Paxlovid)?

Use the medicine as soon as you can, but skip the missed dose if you are more than 8 hours late for the dose. Do not use two doses at one time.

What happens if I overdose (Paxlovid)?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while taking nirmatrelvir and ritonavir (Paxlovid)?

Follow your doctor's instructions about any restrictions on food, beverages, or activity.

What other drugs will affect nirmatrelvir and ritonavir (Paxlovid)?

Sometimes it is not safe to use certain medicines at the same time. Some drugs can affect your blood levels of other drugs you use, which may increase side effects or make the medicines less effective.

Many drugs can affect nirmatrelvir and ritonavir, and some drugs should not be used at the same time. Tell your doctor about all other medicines you use. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed here.

Where can I get more information (Paxlovid)?

Your doctor or pharmacist can provide more information about nirmatrelvir and ritonavir.


Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.
Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.

Health Solutions From Our Sponsors

Reviewed on 10/12/2022

Health Solutions From Our Sponsors