Paxlovid (Eua)
Combination product
Combination of Nirmatrelvir and Ritonavir.
Each component keeps its own pharmacology page; the combination itself adds no new mechanism.
Normal traveler Packs clover
Components (2)
FDA label
Read the full label on DailyMed ↗
| FDA dosing | Population | Start | Target | Max |
|---|---|---|---|---|
| COVID-19, mild-to-moderate (initiate within 5 days of symptom onset) | Adults, eGFR ≥60 | 300 mg nirmatrelvir + 100 mg ritonavir (3 tabs together) BID x 5 days | same | 300/100 mg BID x 5 days |
| COVID-19, mild-to-moderate | Adults, eGFR ≥30–<60 | 150 mg nirmatrelvir + 100 mg ritonavir BID x 5 days | same | 150/100 mg BID x 5 days |
| COVID-19, mild-to-moderate | Adults, eGFR <30 incl. hemodialysis | Day 1: 300/100 mg once; Days 2–5: 150/100 mg QD | same | per tier |
Renal eGFR ≥60–<90: no adjustment. eGFR ≥30–<60: 150/100 mg BID x 5 days. eGFR <30 incl. hemodialysis: 300/100 mg once Day 1, then 150/100 mg QD Days 2–5; on dialysis days give after hemodialysis.
Hepatic Mild–moderate (Child-Pugh A/B): no adjustment. Severe (Child-Pugh C): not recommended (no PK/safety data).
Cannot be started immediately after discontinuing a strong CYP3A inducer (delayed inducer offset).
Instructions
- Start ASAP after COVID-19 diagnosis and within 5 days of symptom onset; complete full 5-day course
- Take all 3 tablets together, with or without food, at ~same time each day
- Swallow whole — do not chew, break, or crush
- Nirmatrelvir must be co-administered with ritonavir (alone → subtherapeutic levels)
- Missed dose ≤8 h: take ASAP; >8 h: skip, do not double
- If hospitalized for severe COVID after starting, complete the 5-day course per provider discretion
Available strengths
- tab 150/100 mg
Contraindications
- Drugs highly CYP3A-dependent where elevated levels are serious/life-threatening: alfuzosin, ranolazine, amiodarone, dronedarone, flecainide, propafenone, quinidine, colchicine (in renal/hepatic impairment), lurasidone, pimozide, silodosin, eplerenone, ivabradine, ergots (DHE, ergotamine, methylergonovine), lovastatin, simvastatin, voclosporin, lomitapide, eletriptan, ubrogepant, finerenone, suzetrigine, naloxegol, sildenafil-for-PAH, triazolam, oral midazolam, flibanserin, tolvaptan
- Strong CYP3A inducers (apalutamide, enzalutamide, carbamazepine, phenobarbital, primidone, phenytoin, rifampin, rifapentine, lumacaftor/ivacaftor, St. John's Wort) — loss of virologic response/resistance; do not start Paxlovid immediately after stopping one
Cautions
- Boxed: review all concomitant meds for CYP3A interactions (worst offenders: calcineurin inhibitors e.g. tacrolimus/cyclosporine, calcium channel blockers)
- Hypersensitivity: anaphylaxis, TEN, SJS reported — discontinue immediately
- Hepatotoxicity (ritonavir): transaminase elevations, hepatitis, jaundice — caution with pre-existing liver disease
- HIV-1 protease-inhibitor resistance risk in uncontrolled/undiagnosed HIV-1
- Ritonavir may reduce combined hormonal contraceptive efficacy — use alternative/barrier method
Adverse reactions
- Dysgeusia (5%)
- Diarrhea (3%)
- Post-EUA: anaphylaxis, TEN/SJS, headache, hypertension, abdominal pain, nausea, vomiting, malaise
Pregnancy Insufficient nirmatrelvir human data; ritonavir observational data show no increased birth-defect risk; untreated COVID-19 in pregnancy itself carries maternal/fetal risk.
Lactation Present in milk in small amounts (infant dose <2% of maternal weight-adjusted); no infant-effect data; weigh benefit vs need.
Cost
| Strength | #/mo | generic $/mo | CostPlus | |
|---|---|---|---|---|
| 150/100 mg | tab | 60 BID | not offered |
Part D rank #276.