(nirmatrelvir tablets; ritonavir tablets)
The following clinically significant adverse reactions are described elsewhere in the labeling:
Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.
The safety of PAXLOVID is based on two Phase 2/3 randomized, placebo-controlled trials in symptomatic adult subjects 18 years of age and older with a laboratory confirmed diagnosis of SARS-CoV-2 infection. Subjects in both studies received PAXLOVID (nirmatrelvir/ritonavir 300 mg/100 mg) or placebo every 12 hours for 5 days for the treatment of mild-to-moderate COVID-19 within 5 days of symptom onset [see Clinical Studies (14)]:
Adverse reactions were those reported while subjects were on study medication and through 28 days after the last dose of study treatment.
In Trial C4671005 (EPIC-HR), 1,038 subjects received PAXLOVID and 1,053 subjects received placebo. The most common adverse reactions (≥1% incidence in the PAXLOVID group and occurring at a greater frequency than in the placebo group) were dysgeusia (5% and <1%, respectively) and diarrhea (3% and 2%, respectively).
Among vaccinated or unvaccinated subjects at standard risk or fully vaccinated subjects with at least 1 risk factor for progression to severe disease in Trial C4671002 (EPIC-SR), 540 subjects received PAXLOVID and 528 subjects received placebo. The adverse reactions observed were consistent with those observed in EPIC-HR.
Trial C4671028 (EPIC-SRI) was a Phase 1, open-label trial that evaluated the effects of severe renal impairment on the pharmacokinetics, safety, and tolerability of PAXLOVID in non-hospitalized adult participants with COVID-19 and severe renal impairment. A total of 15 subjects with severe renal impairment were enrolled in this trial, with 12 subjects receiving intermittent hemodialysis and 3 subjects not on hemodialysis. Subjects received nirmatrelvir/ritonavir 300 mg/100 mg once on Day 1 followed by nirmatrelvir/ritonavir 150 mg/100 mg once daily from Days 2-5. The safety profile of PAXLOVID in subjects with severe renal impairment, including those requiring hemodialysis, was consistent with the safety profile observed in the Phase 2/3 randomized, placebo-controlled trials.
Emergency Use Authorization Experience in Subjects with COVID-19
The following adverse reactions have been identified during use of PAXLOVID under Emergency Use Authorization.
Immune System Disorders: Anaphylaxis, hypersensitivity reactions [see Warnings and Precautions (5.2)]
Skin and Subcutaneous Tissue Disorders: Toxic epidermal necrolysis, Stevens-Johnson syndrome [see Warnings and Precautions (5.2)]
Nervous System Disorders: Headache
Vascular Disorders: Hypertension
Gastrointestinal Disorders: Abdominal pain, nausea, vomiting
General Disorders and Administration Site Conditions: Malaise
PATIENT INFORMATION | ||||||
What is the most important information I should know about PAXLOVID? PAXLOVID can interact with other medicines causing severe or life-threatening side effects or death. It is important to know the medicines that should not be taken with PAXLOVID. Do not take PAXLOVID if:
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These are not the only medicines that may cause serious or life-threatening side effects if taken with PAXLOVID. PAXLOVID may increase or decrease the levels of multiple other medicines. It is very important to tell your healthcare provider about all of the medicines you are taking because additional laboratory tests or changes in the dose of your other medicines may be necessary during treatment with PAXLOVID. Your healthcare provider may also tell you about specific symptoms to watch out for that may indicate that you need to stop or decrease the dose of some of your other medicines.
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What is PAXLOVID? PAXLOVID is not approved for use as pre-exposure or post-exposure treatment for prevention of COVID-19. | ||||||
Before taking PAXLOVID, tell your healthcare provider about all of your medical conditions, including if you:
Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements.
Tell your healthcare provider if you are taking combined birth control (hormonal contraceptive). PAXLOVID may affect how your hormonal contraceptives work. Females who are able to become pregnant should use another effective alternative form of contraception or an additional barrier method of contraception during treatment with PAXLOVID. Talk to your healthcare provider if you have any questions about contraceptive methods that might be right for you. | ||||||
How should I take PAXLOVID?
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If you are prescribed PAXLOVID 300 mg; 100 mg Dose Pack | ||||||
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How to take PAXLOVID 300 mg; 100 mg Dose Pack | ||||||
![]() | Morning Dose: | |||||
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![]() | Bedtime Dose: | |||||
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If you are prescribed PAXLOVID 150 mg; 100 mg Dose Pack | ||||||
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How to take PAXLOVID 150 mg; 100 mg Dose Pack | ||||||
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![]() | Bedtime Dose: | |||||
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If you are prescribed PAXLOVID 300 mg; 100 mg (Day 1) and 150 mg; 100 mg (Days 2-5) | ||||||
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How to take PAXLOVID 300 mg; 100 mg (Day 1) and 150 mg; 100 mg (Days 2-5) | ||||||
![]() | Day 1 (First Day): Take the 2 pink nirmatrelvir tablets and | |||||
![]() | Days 2-5: Take the 1 pink nirmatrelvir tablet and 1 white ritonavir tablet together | |||||
Talk to your healthcare provider if you do not feel better or if you feel worse after 5 days. | ||||||
What are the possible side effects of PAXLOVID? PAXLOVID may cause serious side effects, including:
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The most common side effects of PAXLOVID include: altered sense of taste (such as metallic, bitter taste) and diarrhea. Other possible side effects include:
These are not all of the possible side effects of PAXLOVID. For more information, ask your healthcare provider or pharmacist. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088. | ||||||
How should I store PAXLOVID?
Keep PAXLOVID and all medicines out of the reach of children. | ||||||
General information about the safe and effective use of PAXLOVID. | ||||||
What are the ingredients in PAXLOVID? | ||||||
![]() LAB-1524-5.0 | ||||||
This Patient Information has been approved by the U.S. Food and Drug Administration. Revised: 02/2026
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