

Learn about Paxlovid 5-Day side effects including the metallic taste, diarrhea, and more. Know which symptoms are normal and when to call your doctor.
If your doctor has prescribed Paxlovid 5-Day for your COVID-19 infection, you might be wondering what side effects to expect. The good news: most side effects are mild and go away after you finish the 5-day course. The not-so-great news: one of them — the metallic taste — is hard to ignore.
This guide covers every side effect reported in clinical trials and FDA labeling, so you know exactly what's normal, what's rare, and when you should pick up the phone and call your doctor.
Paxlovid 5-Day is the brand name for Nirmatrelvir/Ritonavir, an antiviral medication made by Pfizer. It's prescribed to treat mild-to-moderate COVID-19 in adults who are at high risk for severe illness. The treatment involves taking three tablets (two Nirmatrelvir + one Ritonavir) twice a day for five days. For a deeper look at how Paxlovid works, check out our detailed guide.
These side effects were reported most frequently in clinical trials. They're generally mild and temporary:
For most people, these side effects are annoying but manageable. They don't usually require you to stop taking the medication.
Serious side effects are rare, but they do exist. Seek medical attention immediately if you experience any of the following:
Patients 65 and older can take Paxlovid at the standard dose (unless they have kidney issues). Older adults may be more susceptible to side effects like diarrhea and should stay well-hydrated.
If you have moderate kidney impairment (eGFR 30-59 mL/min), your doctor will prescribe a reduced dose. Paxlovid is not recommended for people with severe kidney impairment (eGFR below 30 mL/min) because the drug can build up to unsafe levels.
Paxlovid is not recommended for severe liver impairment (Child-Pugh Class C). If you have mild or moderate liver disease, your doctor may still prescribe it but will want to monitor you more closely.
Paxlovid is not recommended during pregnancy unless the potential benefit outweighs the risk. It's also not recommended while breastfeeding or shortly after finishing the course. Talk to your OB-GYN or midwife about the risks and benefits.
Paxlovid has an Emergency Use Authorization (EUA) for patients aged 12 and older who weigh at least 40 kg (about 88 pounds). Side effects in this age group are expected to be similar to adults.
Here are practical tips for dealing with the most common side effects:
In most cases, no. The common side effects are unpleasant but not dangerous, and the benefit of completing the full 5-day course — reducing your risk of hospitalization and death — far outweighs the temporary discomfort.
However, you should stop and call your doctor immediately if you experience:
Do not stop taking Paxlovid just because of the metallic taste or mild diarrhea. Finishing the full course is important for the medication to work properly.
You may have heard about "Paxlovid rebound" — where COVID-19 symptoms return a few days after finishing the course. This has been reported in some patients, but researchers debate whether it's actually caused by Paxlovid or simply part of the natural course of COVID-19 infection. The CDC has noted that rebound can occur whether or not you take antivirals. If your symptoms return after finishing treatment, contact your doctor for guidance.
Paxlovid 5-Day is a safe and effective treatment for high-risk COVID-19 patients. Most side effects — especially the infamous metallic taste — are mild and temporary. Serious reactions are very rare. The most important thing is to complete the full 5-day course and contact your doctor if anything concerns you.
Need to fill your Paxlovid prescription? Use Medfinder to find a pharmacy with Paxlovid 5-Day in stock near you. For information on costs and savings, see our guide on how to save money on Paxlovid 5-Day.
You focus on staying healthy. We'll handle the rest.
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