Paxlovid 5-Day Side Effects: What to Expect and When to Call Your Doctor

What to Know About Paxlovid 5-Day Side Effects

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.

What Is Paxlovid 5-Day?

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.

Common Side Effects of Paxlovid 5-Day

These side effects were reported most frequently in clinical trials. They're generally mild and temporary:

• Dysgeusia (altered or metallic taste) — This is the most talked-about Paxlovid side effect. Many patients describe it as a bitter, metallic, or "chemical" taste that lasts throughout the 5-day treatment. It typically goes away within a few days after finishing the course.
• Diarrhea — Some patients experience loose stools or diarrhea during treatment. It's usually mild and manageable with hydration.
• Hypertension (high blood pressure) — Some patients see a temporary increase in blood pressure. If you already have high blood pressure, monitor it during treatment.
• Myalgia (muscle aches) — Muscle soreness can occur, though it can be hard to tell apart from COVID-19 symptoms themselves.

For most people, these side effects are annoying but manageable. They don't usually require you to stop taking the medication.

Serious Side Effects of Paxlovid 5-Day

Serious side effects are rare, but they do exist. Seek medical attention immediately if you experience any of the following:

• Anaphylaxis or severe allergic reaction — Signs include difficulty breathing, swelling of the face, lips, tongue, or throat, severe rash, or a feeling of throat tightness. Call 911 or go to the emergency room immediately.
• Toxic epidermal necrolysis (TEN) or Stevens-Johnson syndrome (SJS) — These are very rare but serious skin reactions. Watch for widespread skin pain, blistering, peeling skin, or sores on your mouth, eyes, or genitals. Stop taking Paxlovid and seek emergency care.
• Hepatotoxicity (liver damage) — Signs include yellowing of the skin or eyes (jaundice), dark urine, light-colored stools, nausea, or upper right abdominal pain. Contact your doctor promptly.
• HIV-1 drug resistance — The Ritonavir component in Paxlovid is also used in HIV treatment. If you have undiagnosed or uncontrolled HIV, taking Paxlovid could contribute to drug resistance. Your provider should screen for HIV if your status is unknown.

Side Effects in Specific Populations

Older Adults

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.

People With Kidney Disease

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.

People With Liver Disease

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.

Pregnant or Breastfeeding

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.

Teens (12-17)

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.

How to Manage Paxlovid Side Effects

Here are practical tips for dealing with the most common side effects:

The Metallic Taste (Dysgeusia)

• Suck on sugar-free hard candies or mints between doses
• Try strong-flavored foods like citrus fruits or pickles
• Chew gum to mask the taste
• Drink cold beverages — some patients find cold water or iced tea helps
• Remember: it's temporary and will go away after you finish the course

Diarrhea

• Stay hydrated with water, broth, or electrolyte drinks
• Eat bland foods (rice, bananas, toast, applesauce)
• Avoid dairy, greasy, or spicy foods during treatment
• Over-the-counter remedies like Loperamide (Imodium) may help — check with your doctor first

High Blood Pressure

• If you already take blood pressure medication, continue taking it as prescribed
• Monitor your blood pressure at home if you have a cuff
• Reduce sodium intake during the 5-day course
• Contact your doctor if readings are consistently above 180/120

Muscle Aches

• Rest and stay hydrated
• Over-the-counter pain relievers like Acetaminophen (Tylenol) are generally safe to take with Paxlovid
• Avoid NSAIDs like Ibuprofen (Advil) without checking with your doctor, especially if you have kidney issues

Should You Stop Taking Paxlovid Because of 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:

• Signs of a severe allergic reaction (difficulty breathing, facial swelling, severe rash)
• Skin blistering or peeling
• Yellowing of skin or eyes
• Any symptom that feels life-threatening

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.

"Paxlovid Rebound" — Is It a Side Effect?

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.

Final Thoughts

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.