From the Guidelines
Paxlovid can cause several side effects, but the most recent and highest quality study from 2024 1 suggests that the benefits of Paxlovid in reducing the risk of severe COVID-19 typically outweigh these potential side effects for high-risk patients. The most common side effects of Paxlovid include:
- Metallic or bitter taste in the mouth (dysgeusia)
- Diarrhea
- Increased blood pressure
- Muscle aches
- Nausea
- Abdominal pain Most of these side effects are mild to moderate and typically resolve when treatment ends. Paxlovid can also interact with many medications because ritonavir, one of its components, inhibits liver enzymes that metabolize other drugs, as reported in a study from 2024 1. This can lead to increased levels of certain medications in the body, potentially causing serious adverse effects. Before starting Paxlovid, patients should inform their healthcare provider about all medications they're taking, including over-the-counter drugs and supplements. Patients with kidney or liver disease may need dose adjustments, as suggested by a study from 2022 1. If severe side effects occur, such as signs of allergic reaction or severe diarrhea, medical attention should be sought immediately. It is essential to weigh the benefits and risks of Paxlovid, considering the individual patient's condition and medical history, as emphasized in the study from 2024 1. The study from 2024 1 provides the most recent and highest quality evidence, and its findings should be prioritized when making treatment decisions. In general, the side effects of Paxlovid are manageable, and the medication can be an effective treatment option for high-risk patients with COVID-19, as supported by the study from 2024 1.
From the FDA Drug Label
PAXLOVID may cause serious side effects, including: • Allergic reactions, including severe allergic reactions (anaphylaxis) have happened during treatment with PAXLOVID • Liver problems The most common side effects of PAXLOVID include: • altered sense of taste • diarrhea Other possible side effects include: • headache • vomiting • abdominal pain • nausea • high blood pressure • feeling generally unwell
The possible side effects of PAXLOVID include:
- Serious side effects: allergic reactions and liver problems
- Common side effects: altered sense of taste and diarrhea
- Other possible side effects: headache, vomiting, abdominal pain, nausea, high blood pressure, and feeling generally unwell 2
From the Research
Side Effects of Paxlovid
- The side effects of Paxlovid (nirmatrelvir/ritonavir) include dysgeusia and diarrhea, as reported in a study published in 2022 3.
- Treatment-related adverse events such as dysgeusia and diarrhea were more common in the Paxlovid group compared to the placebo group (RR 2.06,95% CI 1.44 to 2.95; 1 study, 2224 participants; moderate-certainty evidence) 3.
- Serious adverse events were less common in the Paxlovid group compared to the placebo group (RR 0.24,95% CI 0.15 to 0.41; 1 study, 2224 participants; low-certainty evidence) 3.
- Treatment-emergent adverse events were similar in the Paxlovid group and the placebo group (RR 0.95% CI 0.82 to 1.10; 1 study, 2224 participants; moderate-certainty evidence) 3.
- Discontinuation of study drug due to adverse events was less common in the Paxlovid group compared to the placebo group (RR 0.49,95% CI 0.30 to 0.80; 1 study, 2224 participants; moderate-certainty evidence) 3.
Drug Interactions
- Nirmatrelvir-ritonavir has a high risk of drug interactions, particularly with medications that are highly dependent on CYP3A4 for clearance 4, 3.
- Ritonavir, a component of Paxlovid, inhibits the metabolizing enzyme cytochrome P450 3A, which can increase the levels of other medications that are metabolized by this enzyme 5.
Safety and Efficacy
- Paxlovid has been shown to be effective in reducing the risk of hospitalization and death in patients with mild to moderate COVID-19 who are at high risk of progression to severe disease 6, 3.
- The safety and efficacy of Paxlovid in certain populations, such as hospitalized patients with COVID-19 and those with certain comorbidities, are still being studied and are not yet well established 3.