apixaban vs nirmatrelvir/ritonavir

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Side-by-side comparison of apixaban and nirmatrelvir/ritonavir. Data from FDA drug databases (Orange Book, NDC Directory, recalls, shortages) covering 20,000+ approved drugs, plus CMS pricing; see our methodology.

moderate Known Drug Interaction

apixaban ↑ apixaban Combined P-gp and strong CYP3A inhibitors increase blood levels of apixaban and increase the risk of bleeding. Dosing recommendations for co-administration of apixaban with PAXLOVID depend on the apixaban dose. Refer to the apixaban product label for more information.

Drug Class
apixaban Direct Oral Anticoagulant (Factor Xa Inhibitor)
nirmatrelvir/ritonavir Antiviral (Protease Inhibitor Combination)
Type
apixaban Prescription
nirmatrelvir/ritonavir Prescription
Summary
apixaban

Apixaban (Eliquis) is a medicine that helps prevent blood clots. It is used to lower the risk of stroke and other serious problems caused by blood clots.

nirmatrelvir/ritonavir

Paxlovid is a medicine used to treat mild to moderate COVID-19 in adults. It helps prevent severe illness, hospitalization, or death in people at high risk.

What It Treats
apixaban

Apixaban is used to lower the chance of stroke in people with an irregular heartbeat called atrial fibrillation. It also prevents blood clots in the legs (deep vein thrombosis or DVT) that can happen after hip or knee replacement surgery. Apixaban is also used to treat DVT and lung clots (pulmonary embolism or PE), and to prevent them from coming back.

nirmatrelvir/ritonavir

Paxlovid treats mild to moderate COVID-19 in adults. You must be at high risk of your illness becoming severe. This includes needing to go to the hospital or possibly dying from COVID-19. Paxlovid is not for preventing COVID-19 before or after exposure.

How It Works
apixaban

Apixaban is a type of drug called a factor Xa inhibitor. It works by blocking a substance in the blood that helps clots form. This helps to keep your blood flowing smoothly.

nirmatrelvir/ritonavir

Paxlovid contains two medicines, nirmatrelvir and ritonavir. Nirmatrelvir stops the virus from multiplying in your body. Ritonavir helps nirmatrelvir stay in your body longer so it can work better.

Common Side Effects
apixaban
  • Bleeding more easily (like nosebleeds or heavier periods)
  • Bruising more easily
nirmatrelvir/ritonavir
  • Change in taste
  • Diarrhea
FAERS Reports
apixaban
  • Atrial Fibrillation 3,970
  • Dyspnoea 3,598
  • Cerebrovascular Accident 3,508
  • Thrombosis 2,806
  • Cardiac Disorder 2,509
nirmatrelvir/ritonavir
  • COVID-19 22,774
  • COVID-19 coming back 20,089
  • Change in taste 7,316
  • Diarrhea 4,003
  • Feeling sick to your stomach 2,620
Serious Warnings
apixaban

Apixaban has two important warnings. First, stopping apixaban too early can raise your risk of blood clots. Don't stop taking it without talking to your doctor. Second, if you have spinal anesthesia or a spinal puncture while taking apixaban, you could get a blood clot around your spine, which can cause long-term paralysis.

nirmatrelvir/ritonavir

Paxlovid can interact with many other medicines, causing serious or life-threatening problems. Before taking Paxlovid, tell your doctor about all the medicines you take. Your doctor may need to adjust the dose of your other medicines or monitor you more closely.

Pregnancy
apixaban

Apixaban is not recommended during pregnancy because it may increase the risk of bleeding during pregnancy and delivery. Talk to your doctor about the risks and benefits of taking apixaban if you are breastfeeding. You may need to stop taking the drug or stop nursing.

nirmatrelvir/ritonavir

There is not enough information about nirmatrelvir's safety during pregnancy. Studies on ritonavir in pregnant women have not shown an increased risk of birth defects. Talk to your doctor about the risks and benefits of taking Paxlovid if you are pregnant or breastfeeding.

Also Compare, Nearby Drugs

How to Read This apixaban vs nirmatrelvir/ritonavir Comparison

apixaban is classified in the Direct Oral Anticoagulant (Factor Xa Inhibitor) drug class, while nirmatrelvir/ritonavir sits within the Antiviral (Protease Inhibitor Combination) class. Drugs from different classes work through distinct mechanisms, so a head-to-head comparison illustrates trade-offs rather than equivalence. Both drugs are prescription-only, so a licensed provider must authorize use.

Adverse event totals above are pulled from the FDA's Adverse Event Reporting System (FAERS). For these top-ranked reactions alone, apixaban has 16,391 submissions while nirmatrelvir/ritonavir has 56,802. Those figures reflect cumulative reporting volume, not per-patient risk, so older, widely dispensed drugs typically look worse on count alone. These two drugs have a known moderate interaction flagged in FDA labeling, attributed to paxlovid blocks the enzymes and proteins that normally clear apixaban from your body, causing the blood thinner to build up. this increases your risk of serious bleeding.. Serious warnings, pregnancy guidance, and contraindications can differ even when indications overlap.

A table cannot represent individual circumstances. Data here is sourced from FDA Structured Product Labels (SPL) and FAERS, both of which update as manufacturers and clinicians submit new information. This registry does not provide medical, treatment, substitution, or medication-change directions for apixaban or nirmatrelvir/ritonavir.

Registry boundary: This comparison displays source-record fields and does not provide individualized medical direction.