Paxlovid is an oral antiviral medication authorized for the treatment of mild to moderate COVID-19. This treatment aims to reduce the likelihood of the illness progressing to severe outcomes, including hospitalization or death. Administered as a prescription medication, it offers a way to manage the disease, especially for individuals at higher risk of complications.
What Paxlovid Is
Paxlovid is a combination of two antiviral medications: nirmatrelvir and ritonavir. Nirmatrelvir targets the virus that causes COVID-19. Ritonavir works to enhance the effectiveness of nirmatrelvir by inhibiting its metabolism in the body. This boosting effect ensures nirmatrelvir remains at therapeutic concentrations for a longer duration. Paxlovid is available as oral tablets, typically supplied in dose packs containing both medications.
Who Can Use Paxlovid
Paxlovid is authorized by the FDA for individuals aged 12 and older who weigh at least 40 kilograms (about 88 pounds). This authorization targets those with mild to moderate COVID-19 who are at a high risk of progressing to severe disease. High-risk factors for severe COVID-19 outcomes include certain underlying medical conditions, such as asthma, diabetes, obesity, or a weakened immune system. A healthcare provider must assess an individual’s medical history and current health status to determine if they meet the eligibility criteria for Paxlovid.
How Paxlovid Works
Paxlovid interferes with the SARS-CoV-2 virus’s ability to replicate. Nirmatrelvir specifically acts as a protease inhibitor. This means it blocks a particular enzyme, the 3CL-like protease, which the virus needs to process its proteins and create new viral particles. By inhibiting this enzyme, nirmatrelvir halts the viral replication cycle.
Ritonavir then slows down the breakdown of nirmatrelvir in the body. This boosting action maintains higher levels of nirmatrelvir, allowing it to continuously suppress viral activity and reduce the overall viral load. This reduction helps the body fight off the infection and can decrease the chances of the disease worsening.
Understanding Side Effects and Drug Interactions
Like all medications, Paxlovid can cause side effects. Common side effects include an altered sense of taste, diarrhea, muscle aches, and elevated blood pressure. More serious but less common side effects can include severe allergic reactions, such as hives, skin rash, or swelling of the face, lips, or throat. Liver problems have also been reported, with symptoms like yellowing of the skin or eyes, dark urine, or abdominal pain.
Paxlovid has potential for interactions with other medications. The ritonavir component is a strong inhibitor of the liver enzyme system CYP3A, which metabolizes many other drugs. Its inhibition can lead to increased concentrations of those drugs, potentially causing serious or life-threatening adverse events. Examples include certain statins, blood thinners, immunosuppressants, and hormonal contraceptives. It is important for individuals to disclose all prescription medications, over-the-counter drugs, vitamins, and herbal supplements to their healthcare provider before starting Paxlovid to assess for potential interactions.
Taking Paxlovid and Next Steps
Paxlovid is taken orally as a five-day course. The standard dosage is two nirmatrelvir tablets and one ritonavir tablet together, twice daily. Begin treatment as soon as possible after a COVID-19 diagnosis and within five days of symptom onset for the most benefit. Complete the full five-day course, even if symptoms improve earlier. Missing doses can reduce effectiveness.
If a dose is missed, take it as soon as remembered, unless it is close to the time for the next scheduled dose, in which case the missed dose should be skipped. After completing the treatment, ongoing communication with a healthcare provider is recommended for monitoring and any necessary follow-up.