🕷️ Crawler Inspector

[Skip to main content](https://www.drugs.com/medical-answers/paxlovid-side-effects-8-key-things-3573430/#content) [](https://www.drugs.com/) [Register](https://www.drugs.com/account/register/) [Sign in](https://www.drugs.com/account/login/) Site navigation - [**Upgrade to a Plus Plan** Remove ads and unlock more features.](https://www.drugs.com/account/plan/?launch=ddc-tier-1) - [Register](https://www.drugs.com/account/register/) [Sign in](https://www.drugs.com/account/login/) - [Drugs A-Z](https://www.drugs.com/drug_information.html) - [Pill Identifier](https://www.drugs.com/pill_identification.html) - [Drug Interaction Checker](https://www.drugs.com/drug_interactions.html) - [Compare Drugs](https://www.drugs.com/compare/) - [News](https://www.drugs.com/news.html) - [Pro Edition](https://www.drugs.com/professionals.html) - [More Resources](https://www.drugs.com/sitemap.html) - [Help & Support](https://www.drugs.com/support/) Close 1. [Home](https://www.drugs.com/) 2. [Paxlovid](https://www.drugs.com/paxlovid.html) 3. FAQ # Paxlovid side effects: 8 key things to know Medically reviewed by [Kristianne Hannemann, PharmD](https://www.drugs.com/support/editor/33/kristianne-hannemann-pharmd.html). Last updated on April 3, 2026. **Official Answer** by Drugs.com ## Key Points - [Paxlovid](https://www.drugs.com/paxlovid.html) (nirmatrelvir and ritonavir) is an oral antiviral medicine used to treat mild-to-moderate COVID-19 in people at high risk for severe illness. - It is fully approved for adults and remains authorized for emergency use in certain adolescents 12 to 17 years old who weigh at least 88 pounds (40 kg). - In high‑risk adults, Paxlovid lowers the chance of hospitalization or death by about 80% or more when started within 5 days of symptoms. - In clinical trials, 2% of people on Paxlovid stopped treatment because of side effects, compared with 4% on placebo (an inactive pill). Paxlovid side effects are usually mild and short‑term, but a few serious problems can occur and some people also notice COVID “rebound” after treatment. For most high‑risk patients, the benefit of avoiding hospitalization and death is much greater than the risk of these side effects when the medicine is taken correctly and drug interactions are checked first. ## Quick side‑effect overview | Type of effect | Examples | How often in studies | What it usually means | |---|---|---|---| | Common, usually mild | Bitter or metallic taste, mild diarrhea, mild nausea, headache, muscle aches | Dysgeusia 6%, diarrhea 3%, high blood pressure 1%, muscle aches 1% | Usually annoying but temporary; most people can finish treatment | | Less common but serious | Severe allergic reaction, serious skin rash, liver injury signs, serious breathing or chest symptoms | Rare; mostly seen in case reports or after approval | Stop Paxlovid and get urgent medical help | ## 8 key things to know about Paxlovid side effects ### 1\. Bad or metallic taste (“Paxlovid mouth”) An altered or bad taste in the mouth is the most commonly reported side effect with Paxlovid. People often describe it as a strong chemical or tonic‑water taste that makes food and drinks less enjoyable. In studies, this side effect happened in about 6 out of every 100 people taking Paxlovid and much less often with placebo. The good news is that it’s temporary and harmless. But that does not make it any easier to tolerate. If you can't tolerate the taste at all contact your doctor right away. #### Ways to help mask the bad taste - Chewing sugar-free gum - Having a supply of sweet hard candies (sugar-free, if preferred) or mints to help mask the taste - Sucking on ice - Brushing your teeth frequently and using mouthwash - Drink plenty of fluids throughout the day Do not stop taking Paxlovid without talking to your healthcare provider, even if the taste is very bothersome. If you keep vomiting or cannot keep your doses down, contact your doctor right away. ### 2\. Diarrhea and stomach upset Diarrhea and other digestive problems can be caused by both COVID‑19 and Paxlovid. In the main clinical trials, diarrhea happened in about 3% of people taking Paxlovid and 2% taking placebo. For most people, diarrhea is mild and stops a short time after finishing treatment. Nausea, stomach pain, or mild vomiting can also occur. #### What you can do - Drink plenty of fluids (water, oral rehydration drinks, clear broths) to replace what you lose. - Eat simple foods that are easy on the stomach, such as toast, crackers, bananas, rice, or applesauce. - Avoid spicy, fatty, or fried foods and alcohol until you feel better. Call your healthcare provider if: - Diarrhea is severe or lasts more than a few days. - You cannot keep fluids down, feel dizzy, or have signs of dehydration (very dry mouth, little or no urine, feeling faint). ### 3\. Blood pressure changes Some people have a rise in blood pressure while taking Paxlovid. In trials, this happened in about 1 out of 100 people on Paxlovid and less than 1 out of 100 on placebo. If you already have high blood pressure or heart disease, this is a side effect to watch more closely. #### What you can do - If you have a home blood pressure monitor, check readings once or twice a day while taking Paxlovid and for a few days after. - Call your doctor if your blood pressure is much higher than usual, you develop new or worse headaches, vision changes, or chest pain. Get emergency help for chest pain, trouble breathing, or signs of a stroke (sudden weakness, trouble speaking, or drooping on one side of the face). ### 4\. Muscle aches and body pain Muscle aches (myalgias) are very common with COVID‑19 itself and can also occur with Paxlovid. In studies, muscle aches were reported in about 1% of people taking Paxlovid and less than 1% taking placebo. Most people can treat mild aches with over‑the‑counter pain relievers such as acetaminophen or ibuprofen, if these are safe for them and their other medical conditions. Call your healthcare provider if: - Muscle or joint pain is severe, - You notice muscle weakness, dark urine, or swelling, or - Pain continues long after you finish Paxlovid or test negative for COVID‑19. These could be signs of another problem that needs medical evaluation. ### 5\. Severe allergic reactions and serious skin problems A severe allergy with Paxlovid treatment is not a common side effect, but, like any severe allergy it can be serious or even deadly. Rarely, severe allergic reactions (which may include anaphylaxis) can happen in people taking Paxlovid, even after taking only one dose. If you’ve had a severe allergic reaction to either active ingredient in Paxlovid (nirmatrelvir or ritonavir) or any other components of the product, you should not take it. This includes rare, severe skin allergies known as [toxic epidermal necrolysis](http://www.drugs.com/cg/toxic-epidermal-necrolysis.html) (TEN) or Stevens-Johnson syndrome. Be sure to let your doctor know if you’ve had any severe allergies to nirmatrelvir or ritonavir (Norvir). Stop taking Paxlovid and call your healthcare provider or 911 right away if you get any of the following symptoms of an allergic reaction: - Hives, skin rash, or other skin reaction like skin peeling or redness - Trouble swallowing or breathing - Swelling of the mouth, tongue, lips, or face - Tightness in the throat - Hoarseness of the voice ### 6\. Liver problems Paxlovid can affect the liver, especially in people who already have liver disease. Significant liver injury is not common, but increases in liver enzymes and cases of hepatitis and jaundice have been reported with ritonavir, one of the active ingredients. Paxlovid is not recommended for people with severe liver disease. If you have any history of liver problems (including hepatitis, cirrhosis, or heavy alcohol use), make sure your healthcare provider knows before prescribing Paxlovid. Tell your healthcare provider right away if you have any symptoms of liver problems, which may include: - Loss of appetite - Nausea or vomiting that does not stop - Yellowing of your skin and the whites of eyes (jaundice) - Dark-colored urine - Pale-colored stools and itchy skin - Stomach area (abdominal) pain ### 7\. Kidney problems The kidneys help clear nirmatrelvir from the body, so kidney function affects how much of the drug stays in your system. If you have reduced kidney function, Paxlovid levels can rise and increase the chance of side effects. - Paxlovid is not recommended for people with severe kidney disease. - A lower dose is needed for those with moderate kidney problems. Before starting Paxlovid, tell your healthcare provider and pharmacist if you have a history of kidney disease or have ever been told you have reduced kidney function. They may order a simple blood test or review your recent lab results to decide whether Paxlovid is safe for you and which dose is best. ### 8\. Resistance to HIV medicines / Drug interactions If you have HIV that has not been treated or diagnosed, you may be at risk of developing resistance to [HIV protease inhibitor](https://www.drugs.com/condition/hiv-infection.html) antiviral medicines if you take Paxlovid. These HIV medicines may not work as well if you take them in the future. Talk to your doctor if you think you've been recently exposed to HIV before taking Paxlovid. You may need to take a different treatment or have additional lab tests. ## Is COVID rebound a side effect of Paxlovid? “COVID rebound” means symptoms or a positive test return after you first get better. Rebound can occur with or without Paxlovid, but it has been seen in some people after treatment. - Data shared with the FDA and other studies suggest that around 10% to 26% of people taking Paxlovid report some form of rebound symptoms or repeat positive tests. - CDC reviews show rebound also occurs in people who never took antivirals, and so far studies have not found a clear link between taking Paxlovid and having rebound. Rebound symptoms are usually mild and last about a week, and hospitalizations during rebound are rare. If you develop rebound: - Follow current public health guidance about re‑isolating and masking. - Contact your healthcare provider if symptoms are severe, you are at very high risk, or you are unsure what to do. Rebound is related to the virus, not a direct toxic side effect of the drug, and most experts still recommend Paxlovid for eligible high‑risk patients because of its strong protection against severe disease. ## Drug interactions There are many drug interactions with Paxlovid, including certain medicines you cannot take with Paxlovid. This means you need to tell your doctor and pharmacist about all of the medicines you take (prescription, over-the-counter (OTC), vitamins and herbal supplements) so a drug interaction review can be completed before you start treatment. There may be treatments you need to temporarily stop, or you may not be able to take Paxlovid at all. Your healthcare provider can review your medications with you. - Drug interactions may lead to side effects because levels of drugs may increase. Also, if drug levels go down, your medicine may not work as well. - You can ask your healthcare provider or pharmacist for a list of medicines that interact with Paxlovid. Do not start or stop any treatments without speaking to your prescriber first while taking Paxlovid. - Tell your healthcare provider if you are taking combination hormonal contraceptive (estrogen and progestin), as Paxlovid can affect how your birth control pills work. Females who can become pregnant should use another effective alternative form of contraception or an additional barrier method of contraception (such as a condom). This is not all the information you need to know about [Paxlovid](https://www.drugs.com/paxlovid.html) or COVID-19 for safe and effective use and does not take the place of your healthcare provider's directions. Review the full product information and discuss this information and any questions you have with your doctor or other health care provider. References - Smith, D. J., Lambrou, A., & Patel, P. (2023, December 22). SARS-CoV-2 rebound with and without use of COVID-19 oral antivirals. Centers for Disease Control and Prevention. <https://www.cdc.gov/mmwr/volumes/72/wr/mm7251a1.htm> - Schiffman SS, Zervakis J, Heffron S, Heald AE. Effect of protease inhibitors on the sense of taste. Nutrition. 1999 Oct;15(10):767-72. doi: 10.1016/s0899-9007(99)00152-5. PMID: 10501290. - Frequently Asked Questions on the Emergency Use Authorization for Paxlovid for Treatment of COVID-19. Revised: 11/1/2023. US Food and Drug Administration (FDA). Accessed Nov. 6, 2023 at https://www.fda.gov/media/155052/download - COVID-19: Symptoms, Prevention and Risks. Drugs.com. Accessed Apr 17, 2023 at https://www.drugs.com/article/covid-19-symptoms-prevention.html - Symptoms of COVID-19. June 25, 2024. US Centers for Disease Control and Prevention (CDC). Accessed Oct 23, 2024 at <https://www.cdc.gov/covid/signs-symptoms/> - Fact Sheet for patients, parents and caregivers. Emergency Use Authorization for Paxlovid. Revised: 02/2023. Pfizer Inc. Accessed Apr 17, 2023 at <https://labeling.pfizer.com/ShowLabeling.aspx?id=16473> - Paxlovid for Treatment of COVID-19. The Medical Letter. Issue 1642. Jan 24, 2022. Accessed Apr 17, 2023. - Paxlovid \[package insert\]. Updated February 2026. Pfizer Laboratories Div Pfizer Inc. Accessed on April 3, 2026 at <https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=8a99d6d6-fd9e-45bb-b1bf-48c7f761232a> - Pfizer. (2022, June 14). Pfizer reports additional data on PAXLOVID™ supporting upcoming New Drug Application submission to U.S. FDA \[Press release\]. <https://www.pfizer.com/news/press-release/press-release-detail/pfizer-reports-additional-data-paxlovidtm-supporting> - Reference List Entry: Pfizer. (2023, May 25). Pfizer’s PAXLOVID™ receives FDA approval for adult patients at high risk of progression to severe COVID-19 \[Press release\]. <https://www.pfizer.com/news/press-release/press-release-detail/pfizers-paxlovidtm-receives-fda-approval-adult-patients> - Pannu, V., Udongwo, N., Imburgio, S., Johal, A., Mararenko, A., Pozdniakova, H., Amin, T., Patel, S., Hossain, M., Mushtaq, A., Liu, E., Fune, J. M., & Heaton, J. (2024). Adverse Events of SARS-CoV-2 Therapy: A Pharmacovigilance Study of the FAERS Database. The Annals of pharmacotherapy, 58(2), 105–109. <https://doi.org/10.1177/10600280231169256> - University of California, San Francisco. (2024, January 4). Study finds Paxlovid treatment does not reduce risk of long COVID. <https://www.ucsf.edu/news/2024/01/426906/study-finds-paxlovid-treatment-does-not-reduce-risk-long-covid> ## Read next ## How fast does Paxlovid work? Paxlovid starts fighting the COVID virus soon after you take the first dose, but you may not feel better right away. Most people who improve on Paxlovid notice some symptom relief within about 1 to 2 days, and feel much better within about 3 to 5 days. [Continue reading](https://www.drugs.com/medical-answers/fast-paxlovid-work-3570271/) ## Does Paxlovid make you less contagious? Taking Paxlovid (nirmatrelvir and ritonavir) to treat COVID-19 within 5 days of symptoms can make you less contagious sooner than if you do not take it, but it is still important to follow public health recommendations if you are sick. One study found that taking Paxlovid three days after symptoms started reduced how contagious people were by 12% in those who did not experience rebound. [Continue reading](https://www.drugs.com/medical-answers/paxlovid-make-you-contagious-3578401/) ## Can you take Paxlovid twice if COVID rebounds? No, a second round of Paxlovid treatment is not needed after the initial 5-day treatment if COVID rebound occurs. Case reports suggest that most people who develop COVID rebound after completing 5 days of treatment have either no symptoms or mild illness. To date, there is no association between Paxlovid and COVID rebound. [Continue reading](https://www.drugs.com/medical-answers/you-paxlovid-covid-rebounds-3569972/) ## See also: ### [Vyndaqel](https://www.drugs.com/vyndaqel.html) Vyndaqel (tafamidis meglumine) is a transthyretin stabilizer that may be given to reduce death or ... **Reviews & ratings** [4 Reviews](https://www.drugs.com/comments/tafamidis/vyndaqel.html) [View more](https://www.drugs.com/vyndaqel.html) ### [Attruby](https://www.drugs.com/attruby.html) Attruby (acoramidis) tablets are used to treat cardiomyopathy of wild-type or hereditary ... **Reviews & ratings** [Add a review](https://www.drugs.com/members_comments_add/?ddc_id=4656&brand_name_id=20932&condition_id=0) [View more](https://www.drugs.com/attruby.html) ### [Amvuttra](https://www.drugs.com/amvuttra.html) Amvuttra is used to treat polyneuropathy associated with hereditary transthyretin-mediated ... **Reviews & ratings** [1 Review](https://www.drugs.com/comments/vutrisiran/amvuttra.html) [View more](https://www.drugs.com/amvuttra.html) ### [Wainua](https://www.drugs.com/wainua.html) Wainua (eplontersen) is used to treat polyneuropathy of hereditary transthyretin-mediated ... **Reviews & ratings** [1 Review](https://www.drugs.com/comments/eplontersen/wainua.html) [View more](https://www.drugs.com/wainua.html) ### [Onpattro](https://www.drugs.com/onpattro.html) Onpattro is used to treat polyneuropathy in adults with hereditary transthyretin-mediated ... **Reviews & ratings** [Add a review](https://www.drugs.com/members_comments_add/?ddc_id=3948&brand_name_id=18924&condition_id=0) [View more](https://www.drugs.com/onpattro.html) ### [Inotersen](https://www.drugs.com/inotersen.html) Inotersen (brand name Tegsedi) is a self-administered, once-weekly injection that may be used to ... **Reviews & ratings** [Add a review](https://www.drugs.com/members_comments_add/?ddc_id=3969&brand_name_id=0&condition_id=0) [View more](https://www.drugs.com/inotersen.html) ### [Patisiran](https://www.drugs.com/patisiran.html) Patisiran (brand name Onpattro) is an injectable treatment for polyneuropathy caused by hereditary ... **Reviews & ratings** [Add a review](https://www.drugs.com/members_comments_add/?ddc_id=3948&brand_name_id=0&condition_id=0) [View more](https://www.drugs.com/patisiran.html) ### [Eplontersen](https://www.drugs.com/eplontersen.html) Eplontersen (Wainua) is used to treat polyneuropathy of hereditary transthyretin-mediated ... **Reviews & ratings** [1 Review](https://www.drugs.com/comments/eplontersen/) [View more](https://www.drugs.com/eplontersen.html) ### [Vutrisiran](https://www.drugs.com/vutrisiran.html) Vutrisiran (brand name Amvuttra) is used to treat nerve damage associated with hereditary ... **Reviews & ratings** [1 Review](https://www.drugs.com/comments/vutrisiran/) [View more](https://www.drugs.com/vutrisiran.html) ### [Xenazine](https://www.drugs.com/xenazine.html) Xenazine (tetrabenazine) is used to treat Huntington's chorea (uncontrolled muscle ... **Reviews & ratings** [2 Reviews](https://www.drugs.com/comments/tetrabenazine/xenazine.html) [View more](https://www.drugs.com/xenazine.html) ### [Ingrezza](https://www.drugs.com/ingrezza.html) Ingrezza (valbenazine) is used to treat tardive dyskinesia (TD) and chorea associated with ... **Reviews & ratings** 6\.2 / 10 [23 Reviews](https://www.drugs.com/comments/valbenazine/ingrezza.html) [View more](https://www.drugs.com/ingrezza.html) ### [Vitamin B6](https://www.drugs.com/mtm/vitamin-b6.html) Vitamin B6 is used for anemia, dietary supplementation, drug induced vitamin/mineral deficiency ... **Reviews & ratings** [3 Reviews](https://www.drugs.com/comments/pyridoxine/vitamin-b6.html) [View more](https://www.drugs.com/mtm/vitamin-b6.html) ### [Gocovri](https://www.drugs.com/gocovri.html) Gocovri (amantadine) is used in the treatment of Parkinson's disease. Includes Gocovri side ... **Reviews & ratings** [6 Reviews](https://www.drugs.com/comments/amantadine/gocovri.html) [View more](https://www.drugs.com/gocovri.html) ### [Symmetrel](https://www.drugs.com/cons/symmetrel.html) Symmetrel is used for extrapyramidal reaction, parkinson's disease **Reviews & ratings** [3 Reviews](https://www.drugs.com/comments/amantadine/symmetrel.html) [View more](https://www.drugs.com/cons/symmetrel.html) ### [Osmolex ER](https://www.drugs.com/mtm/osmolex-er.html) Osmolex ER is used for extrapyramidal reaction, parkinson's disease **Reviews & ratings** [Add a review](https://www.drugs.com/members_comments_add/?ddc_id=148&brand_name_id=18795&condition_id=0) [View more](https://www.drugs.com/mtm/osmolex-er.html) ### [Valbenazine](https://www.drugs.com/valbenazine.html) Valbenazine (Ingrezza) is used to treat tardive dyskinesia (TD) and chorea associated with ... **Reviews & ratings** 6\.3 / 10 [24 Reviews](https://www.drugs.com/comments/valbenazine/) [View more](https://www.drugs.com/valbenazine.html) ### [Vitamin e](https://www.drugs.com/vitamin_e.html) Vitamin E is an antioxidant that occurs naturally in some foods and is used to treat or prevent ... **Reviews & ratings** [7 Reviews](https://www.drugs.com/comments/vitamin-e/) [View more](https://www.drugs.com/vitamin_e.html) ### [Pyridoxine](https://www.drugs.com/mtm/pyridoxine.html) Pyridoxine is used for anemia, dietary supplementation, drug induced vitamin/mineral deficiency ... **Reviews & ratings** [4 Reviews](https://www.drugs.com/comments/pyridoxine/) [View more](https://www.drugs.com/mtm/pyridoxine.html) ### [Amantadine](https://www.drugs.com/amantadine.html) Easy-to-read patient leaflet for amantadine. Includes indications, proper use, special ... **Reviews & ratings** 6\.7 / 10 [63 Reviews](https://www.drugs.com/comments/amantadine/) [View more](https://www.drugs.com/amantadine.html) ### Related medical questions - [How effective is Paxlovid for COVID-19?](https://www.drugs.com/medical-answers/effective-paxlovid-covid-19-3564414/) - [When should you take Paxlovid?](https://www.drugs.com/medical-answers/when-you-take-paxlovid-3577824/) - [How do Paxlovid and molnupiravir compare for COVID-19?](https://www.drugs.com/medical-answers/how-paxlovid-molnupiravir-compare-covid-19-3577831/) - [Does Paxlovid prevent Long COVID?](https://www.drugs.com/medical-answers/paxlovid-prevent-long-covid-3575586/) - [Can pharmacists prescribe Paxlovid?](https://www.drugs.com/medical-answers/pharmacists-prescribe-paxlovid-3577842/) - [Should I take Paxlovid after a Positive COVID-19 Test?](https://www.drugs.com/insights/paxlovid-after-positive-covid-19-test-3571219/) - [What Drugs Prevent or Treat Serious COVID-19 Cases](https://www.drugs.com/insights/medications-prevent-treat-serious-covid-19-cases-3571309/) ### Drug information - [Paxlovid Information for Consumers](https://www.drugs.com/paxlovid.html) - [Paxlovid prescribing info & package insert](https://www.drugs.com/pro/paxlovid.html) (for Health Professionals) - [Side Effects of Paxlovid](https://www.drugs.com/sfx/paxlovid-side-effects.html) (detailed) - [Paxlovid user reviews](https://www.drugs.com/comments/nirmatrelvir-ritonavir/paxlovid.html) (541) ### Related support groups - [Paxlovid](https://www.drugs.com/answers/support-group/paxlovid/) (19 questions, 22 members) [Medical Disclaimer](https://www.drugs.com/support/disclaimer.html) **Drugs.com Mobile App** Access drug & treatment information, identify pills, check interactions and set up personal medication records. [Download the Medication Guide app on iTunes ](https://apps.apple.com/us/app/drugs-com-medication-guide/id599471042?platform=iphone) [Download the Medication Guide app on the Google Play store ](https://play.google.com/store/apps/details?id=com.drugscom.app)  [Drugs.com ](https://www.drugs.com/) **About** - [About Drugs.com](https://www.drugs.com/support/about.html) - [Advertising policy](https://www.drugs.com/support/advertising.html) - [Attribution & citations](https://www.drugs.com/support/citations.html) - [Drugs.com Podcast](https://podcasts.drugs.com/) **Terms & privacy** - [Terms of use](https://www.drugs.com/support/terms.html) - [Editorial policy](https://www.drugs.com/support/editorial-policy.html) - [Privacy policy](https://www.drugs.com/support/privacy.html) - [Privacy settings](https://www.drugs.com/medical-answers/paxlovid-side-effects-8-key-things-3573430/) **Support** - [Help center](https://www.drugs.com/support/) - [Sitemap](https://www.drugs.com/sitemap.html) - [Contact us](https://www.drugs.com/support/contact.html) - [Accessibility](https://www.drugs.com/support/accessibility.html) - [Subscribe to Drugs.com newsletters](https://www.drugs.com/newsletters/) - [Follow Drugs.com on Facebook](https://www.facebook.com/Drugscom) - [Follow Drugs.com on X (Twitter)](https://x.com/drugscom) - [Follow Drugs.com on Instagram](https://www.instagram.com/drugs.com_official/) - [Follow Drugs.com on YouTube](https://www.youtube.com/user/drugscom) - [Follow Drugs.com on Pinterest](https://www.pinterest.com/drugscom/) [Subscribe to our newsletter](https://www.drugs.com/newsletters/) for the latest medication news, new drug approvals and FDA alerts. **Drugs.com** provides accurate and independent information on more than 24,000 prescription drugs, over-the-counter medicines and natural products. This material is provided for educational purposes only and is not intended for medical advice, diagnosis or treatment. Data sources include Micromedex (updated Mar 31, 2026), Cerner Multum™ (updated Mar 29, 2026), ASHP (updated Mar 10, 2026) and others. [](https://privacy.truste.com/privacy-seal/validation?rid=d18cba4a-afc4-4863-af81-8262bb120271)  [](https://aacihealthcare.com/certificates/c173-2022-trust-us/) [](https://www.drugs.com/support/privacy/advertising.html) Copyright © 2000-2026 Drugs.com. All rights reserved.

**Official Answer** by Drugs.com ## Key Points - [Paxlovid](https://www.drugs.com/paxlovid.html) (nirmatrelvir and ritonavir) is an oral antiviral medicine used to treat mild-to-moderate COVID-19 in people at high risk for severe illness. - It is fully approved for adults and remains authorized for emergency use in certain adolescents 12 to 17 years old who weigh at least 88 pounds (40 kg). - In high‑risk adults, Paxlovid lowers the chance of hospitalization or death by about 80% or more when started within 5 days of symptoms. - In clinical trials, 2% of people on Paxlovid stopped treatment because of side effects, compared with 4% on placebo (an inactive pill). Paxlovid side effects are usually mild and short‑term, but a few serious problems can occur and some people also notice COVID “rebound” after treatment. For most high‑risk patients, the benefit of avoiding hospitalization and death is much greater than the risk of these side effects when the medicine is taken correctly and drug interactions are checked first. ## Quick side‑effect overview | Type of effect | Examples | How often in studies | What it usually means | |---|---|---|---| | Common, usually mild | Bitter or metallic taste, mild diarrhea, mild nausea, headache, muscle aches | Dysgeusia 6%, diarrhea 3%, high blood pressure 1%, muscle aches 1% | Usually annoying but temporary; most people can finish treatment | | Less common but serious | Severe allergic reaction, serious skin rash, liver injury signs, serious breathing or chest symptoms | Rare; mostly seen in case reports or after approval | Stop Paxlovid and get urgent medical help | ## 8 key things to know about Paxlovid side effects ### 1\. Bad or metallic taste (“Paxlovid mouth”) An altered or bad taste in the mouth is the most commonly reported side effect with Paxlovid. People often describe it as a strong chemical or tonic‑water taste that makes food and drinks less enjoyable. In studies, this side effect happened in about 6 out of every 100 people taking Paxlovid and much less often with placebo. The good news is that it’s temporary and harmless. But that does not make it any easier to tolerate. If you can't tolerate the taste at all contact your doctor right away. #### Ways to help mask the bad taste - Chewing sugar-free gum - Having a supply of sweet hard candies (sugar-free, if preferred) or mints to help mask the taste - Sucking on ice - Brushing your teeth frequently and using mouthwash - Drink plenty of fluids throughout the day Do not stop taking Paxlovid without talking to your healthcare provider, even if the taste is very bothersome. If you keep vomiting or cannot keep your doses down, contact your doctor right away. ### 2\. Diarrhea and stomach upset Diarrhea and other digestive problems can be caused by both COVID‑19 and Paxlovid. In the main clinical trials, diarrhea happened in about 3% of people taking Paxlovid and 2% taking placebo. For most people, diarrhea is mild and stops a short time after finishing treatment. Nausea, stomach pain, or mild vomiting can also occur. #### What you can do - Drink plenty of fluids (water, oral rehydration drinks, clear broths) to replace what you lose. - Eat simple foods that are easy on the stomach, such as toast, crackers, bananas, rice, or applesauce. - Avoid spicy, fatty, or fried foods and alcohol until you feel better. Call your healthcare provider if: - Diarrhea is severe or lasts more than a few days. - You cannot keep fluids down, feel dizzy, or have signs of dehydration (very dry mouth, little or no urine, feeling faint). ### 3\. Blood pressure changes Some people have a rise in blood pressure while taking Paxlovid. In trials, this happened in about 1 out of 100 people on Paxlovid and less than 1 out of 100 on placebo. If you already have high blood pressure or heart disease, this is a side effect to watch more closely. #### What you can do - If you have a home blood pressure monitor, check readings once or twice a day while taking Paxlovid and for a few days after. - Call your doctor if your blood pressure is much higher than usual, you develop new or worse headaches, vision changes, or chest pain. Get emergency help for chest pain, trouble breathing, or signs of a stroke (sudden weakness, trouble speaking, or drooping on one side of the face). ### 4\. Muscle aches and body pain Muscle aches (myalgias) are very common with COVID‑19 itself and can also occur with Paxlovid. In studies, muscle aches were reported in about 1% of people taking Paxlovid and less than 1% taking placebo. Most people can treat mild aches with over‑the‑counter pain relievers such as acetaminophen or ibuprofen, if these are safe for them and their other medical conditions. Call your healthcare provider if: - Muscle or joint pain is severe, - You notice muscle weakness, dark urine, or swelling, or - Pain continues long after you finish Paxlovid or test negative for COVID‑19. These could be signs of another problem that needs medical evaluation. ### 5\. Severe allergic reactions and serious skin problems A severe allergy with Paxlovid treatment is not a common side effect, but, like any severe allergy it can be serious or even deadly. Rarely, severe allergic reactions (which may include anaphylaxis) can happen in people taking Paxlovid, even after taking only one dose. If you’ve had a severe allergic reaction to either active ingredient in Paxlovid (nirmatrelvir or ritonavir) or any other components of the product, you should not take it. This includes rare, severe skin allergies known as [toxic epidermal necrolysis](http://www.drugs.com/cg/toxic-epidermal-necrolysis.html) (TEN) or Stevens-Johnson syndrome. Be sure to let your doctor know if you’ve had any severe allergies to nirmatrelvir or ritonavir (Norvir). Stop taking Paxlovid and call your healthcare provider or 911 right away if you get any of the following symptoms of an allergic reaction: - Hives, skin rash, or other skin reaction like skin peeling or redness - Trouble swallowing or breathing - Swelling of the mouth, tongue, lips, or face - Tightness in the throat - Hoarseness of the voice ### 6\. Liver problems Paxlovid can affect the liver, especially in people who already have liver disease. Significant liver injury is not common, but increases in liver enzymes and cases of hepatitis and jaundice have been reported with ritonavir, one of the active ingredients. Paxlovid is not recommended for people with severe liver disease. If you have any history of liver problems (including hepatitis, cirrhosis, or heavy alcohol use), make sure your healthcare provider knows before prescribing Paxlovid. Tell your healthcare provider right away if you have any symptoms of liver problems, which may include: - Loss of appetite - Nausea or vomiting that does not stop - Yellowing of your skin and the whites of eyes (jaundice) - Dark-colored urine - Pale-colored stools and itchy skin - Stomach area (abdominal) pain ### 7\. Kidney problems The kidneys help clear nirmatrelvir from the body, so kidney function affects how much of the drug stays in your system. If you have reduced kidney function, Paxlovid levels can rise and increase the chance of side effects. - Paxlovid is not recommended for people with severe kidney disease. - A lower dose is needed for those with moderate kidney problems. Before starting Paxlovid, tell your healthcare provider and pharmacist if you have a history of kidney disease or have ever been told you have reduced kidney function. They may order a simple blood test or review your recent lab results to decide whether Paxlovid is safe for you and which dose is best. ### 8\. Resistance to HIV medicines / Drug interactions If you have HIV that has not been treated or diagnosed, you may be at risk of developing resistance to [HIV protease inhibitor](https://www.drugs.com/condition/hiv-infection.html) antiviral medicines if you take Paxlovid. These HIV medicines may not work as well if you take them in the future. Talk to your doctor if you think you've been recently exposed to HIV before taking Paxlovid. You may need to take a different treatment or have additional lab tests. ## Is COVID rebound a side effect of Paxlovid? “COVID rebound” means symptoms or a positive test return after you first get better. Rebound can occur with or without Paxlovid, but it has been seen in some people after treatment. - Data shared with the FDA and other studies suggest that around 10% to 26% of people taking Paxlovid report some form of rebound symptoms or repeat positive tests. - CDC reviews show rebound also occurs in people who never took antivirals, and so far studies have not found a clear link between taking Paxlovid and having rebound. Rebound symptoms are usually mild and last about a week, and hospitalizations during rebound are rare. If you develop rebound: - Follow current public health guidance about re‑isolating and masking. - Contact your healthcare provider if symptoms are severe, you are at very high risk, or you are unsure what to do. Rebound is related to the virus, not a direct toxic side effect of the drug, and most experts still recommend Paxlovid for eligible high‑risk patients because of its strong protection against severe disease. ## Drug interactions There are many drug interactions with Paxlovid, including certain medicines you cannot take with Paxlovid. This means you need to tell your doctor and pharmacist about all of the medicines you take (prescription, over-the-counter (OTC), vitamins and herbal supplements) so a drug interaction review can be completed before you start treatment. There may be treatments you need to temporarily stop, or you may not be able to take Paxlovid at all. Your healthcare provider can review your medications with you. - Drug interactions may lead to side effects because levels of drugs may increase. Also, if drug levels go down, your medicine may not work as well. - You can ask your healthcare provider or pharmacist for a list of medicines that interact with Paxlovid. Do not start or stop any treatments without speaking to your prescriber first while taking Paxlovid. - Tell your healthcare provider if you are taking combination hormonal contraceptive (estrogen and progestin), as Paxlovid can affect how your birth control pills work. Females who can become pregnant should use another effective alternative form of contraception or an additional barrier method of contraception (such as a condom). This is not all the information you need to know about [Paxlovid](https://www.drugs.com/paxlovid.html) or COVID-19 for safe and effective use and does not take the place of your healthcare provider's directions. Review the full product information and discuss this information and any questions you have with your doctor or other health care provider. References - Smith, D. J., Lambrou, A., & Patel, P. (2023, December 22). SARS-CoV-2 rebound with and without use of COVID-19 oral antivirals. Centers for Disease Control and Prevention. <https://www.cdc.gov/mmwr/volumes/72/wr/mm7251a1.htm> - Schiffman SS, Zervakis J, Heffron S, Heald AE. Effect of protease inhibitors on the sense of taste. Nutrition. 1999 Oct;15(10):767-72. doi: 10.1016/s0899-9007(99)00152-5. PMID: 10501290. - Frequently Asked Questions on the Emergency Use Authorization for Paxlovid for Treatment of COVID-19. Revised: 11/1/2023. US Food and Drug Administration (FDA). Accessed Nov. 6, 2023 at https://www.fda.gov/media/155052/download - COVID-19: Symptoms, Prevention and Risks. Drugs.com. Accessed Apr 17, 2023 at https://www.drugs.com/article/covid-19-symptoms-prevention.html - Symptoms of COVID-19. June 25, 2024. US Centers for Disease Control and Prevention (CDC). Accessed Oct 23, 2024 at <https://www.cdc.gov/covid/signs-symptoms/> - Fact Sheet for patients, parents and caregivers. Emergency Use Authorization for Paxlovid. Revised: 02/2023. Pfizer Inc. Accessed Apr 17, 2023 at <https://labeling.pfizer.com/ShowLabeling.aspx?id=16473> - Paxlovid for Treatment of COVID-19. The Medical Letter. Issue 1642. Jan 24, 2022. Accessed Apr 17, 2023. - Paxlovid \[package insert\]. Updated February 2026. Pfizer Laboratories Div Pfizer Inc. Accessed on April 3, 2026 at <https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=8a99d6d6-fd9e-45bb-b1bf-48c7f761232a> - Pfizer. (2022, June 14). Pfizer reports additional data on PAXLOVID™ supporting upcoming New Drug Application submission to U.S. FDA \[Press release\]. <https://www.pfizer.com/news/press-release/press-release-detail/pfizer-reports-additional-data-paxlovidtm-supporting> - Reference List Entry: Pfizer. (2023, May 25). Pfizer’s PAXLOVID™ receives FDA approval for adult patients at high risk of progression to severe COVID-19 \[Press release\]. <https://www.pfizer.com/news/press-release/press-release-detail/pfizers-paxlovidtm-receives-fda-approval-adult-patients> - Pannu, V., Udongwo, N., Imburgio, S., Johal, A., Mararenko, A., Pozdniakova, H., Amin, T., Patel, S., Hossain, M., Mushtaq, A., Liu, E., Fune, J. M., & Heaton, J. (2024). Adverse Events of SARS-CoV-2 Therapy: A Pharmacovigilance Study of the FAERS Database. The Annals of pharmacotherapy, 58(2), 105–109. <https://doi.org/10.1177/10600280231169256> - University of California, San Francisco. (2024, January 4). Study finds Paxlovid treatment does not reduce risk of long COVID. <https://www.ucsf.edu/news/2024/01/426906/study-finds-paxlovid-treatment-does-not-reduce-risk-long-covid> ## Read next ## How fast does Paxlovid work? Paxlovid starts fighting the COVID virus soon after you take the first dose, but you may not feel better right away. Most people who improve on Paxlovid notice some symptom relief within about 1 to 2 days, and feel much better within about 3 to 5 days. [Continue reading](https://www.drugs.com/medical-answers/fast-paxlovid-work-3570271/) ## Does Paxlovid make you less contagious? Taking Paxlovid (nirmatrelvir and ritonavir) to treat COVID-19 within 5 days of symptoms can make you less contagious sooner than if you do not take it, but it is still important to follow public health recommendations if you are sick. One study found that taking Paxlovid three days after symptoms started reduced how contagious people were by 12% in those who did not experience rebound. [Continue reading](https://www.drugs.com/medical-answers/paxlovid-make-you-contagious-3578401/) ## Can you take Paxlovid twice if COVID rebounds? No, a second round of Paxlovid treatment is not needed after the initial 5-day treatment if COVID rebound occurs. Case reports suggest that most people who develop COVID rebound after completing 5 days of treatment have either no symptoms or mild illness. To date, there is no association between Paxlovid and COVID rebound. [Continue reading](https://www.drugs.com/medical-answers/you-paxlovid-covid-rebounds-3569972/) ## See also: ### Related medical questions - [How effective is Paxlovid for COVID-19?](https://www.drugs.com/medical-answers/effective-paxlovid-covid-19-3564414/) - [When should you take Paxlovid?](https://www.drugs.com/medical-answers/when-you-take-paxlovid-3577824/) - [How do Paxlovid and molnupiravir compare for COVID-19?](https://www.drugs.com/medical-answers/how-paxlovid-molnupiravir-compare-covid-19-3577831/) - [Does Paxlovid prevent Long COVID?](https://www.drugs.com/medical-answers/paxlovid-prevent-long-covid-3575586/) - [Can pharmacists prescribe Paxlovid?](https://www.drugs.com/medical-answers/pharmacists-prescribe-paxlovid-3577842/) - [Should I take Paxlovid after a Positive COVID-19 Test?](https://www.drugs.com/insights/paxlovid-after-positive-covid-19-test-3571219/) - [What Drugs Prevent or Treat Serious COVID-19 Cases](https://www.drugs.com/insights/medications-prevent-treat-serious-covid-19-cases-3571309/) ### Drug information - [Paxlovid Information for Consumers](https://www.drugs.com/paxlovid.html) - [Paxlovid prescribing info & package insert](https://www.drugs.com/pro/paxlovid.html) (for Health Professionals) - [Side Effects of Paxlovid](https://www.drugs.com/sfx/paxlovid-side-effects.html) (detailed) - [Paxlovid user reviews](https://www.drugs.com/comments/nirmatrelvir-ritonavir/paxlovid.html) (541) ### Related support groups - [Paxlovid](https://www.drugs.com/answers/support-group/paxlovid/) (19 questions, 22 members) [Medical Disclaimer](https://www.drugs.com/support/disclaimer.html)