Paxlovid (Nirmatrelvir & Ritonavir) – Antiviral Treatment for COVID-19

Paxlovid is an FDA-approved antiviral combination containing nirmatrelvir and ritonavir for treating mild-to-moderate COVID-19 in high-risk patients. This oral medication reduces hospitalization and death risk by 86% when started within 5 days of symptom onset. The dual-action formula inhibits SARS-CoV-2 replication while boosting therapeutic drug levels. Packaged as co-administered tablets, Paxlovid provides a complete 5-day treatment course for eligible patients meeting clinical criteria.

Uses of Paxlovid:

• Treatment of acute COVID-19 infection in high-risk individuals
• Reduction of hospitalization/mortality risk in eligible patients
• Management of mild-to-moderate SARS-CoV-2 infection

Benefits of Paxlovid:

• 86% reduction in COVID-19 hospitalization/death
• Convenient oral administration (no injections required)
• Complete 5-day treatment course
• Effective against Omicron variants (when initiated early)

Side Effects of Paxlovid:

Common side effects: Dysgeusia (metallic taste, 6%), diarrhea (3%), hypertension (1%)

Serious side effects:

• Hypersensitivity reactions (0.5%)
• Hepatotoxicity (0.3%)
• HIV drug resistance (in undiagnosed HIV patients)

How to Take Paxlovid?

• Standard dose: 2 nirmatrelvir (150mg) + 1 ritonavir (100mg) twice daily
• Start within 5 days of symptom onset
• Take with or without food
• Swallow tablets whole with water
• Renal adjustment: Reduced dose for eGFR 30-60mL/min

How Paxlovid Works?

1. Nirmatrelvir: Inhibits SARS-CoV-2 main protease (3CL^pro), blocking viral replication
2. Ritonavir: Pharmacokinetic booster that inhibits CYP3A metabolism of nirmatrelvir

This dual mechanism achieves therapeutic drug levels to effectively combat COVID-19 infection.

Safety Advice:

• Contraindications: Severe renal/hepatic impairment, certain drug interactions
• Pregnancy: Risk-benefit assessment required
• Monitoring: LFTs for hepatic symptoms, COVID rebound evaluation
• Drug Interactions: 150+ significant interactions – verify all medications

What If You Miss a Dose?

Within 8 hours: Take immediately
After 8 hours: Skip dose and resume schedule
Never double dose to compensate

FAQs:

Q1. Who qualifies for Paxlovid treatment?

High-risk patients aged ≥12 years (≥40kg) with mild-to-moderate COVID-19 and ≥1 risk factor (age ≥50, chronic conditions, immunocompromised status).

Q2. Does Paxlovid cause COVID rebound?

Rebound occurs in 2-6% of cases, typically mild and self-limiting within 3 days. No evidence supports retreatment.

Q3. How does Paxlovid compare to molnupiravir?

Paxlovid shows superior efficacy (86% vs 30% risk reduction) and better safety profile than molnupiravir.

Q4. Can I take statins with Paxlovid?

Avoid simvastatin/lovastatin. Other statins may require dose adjustment – consult your physician.

Q5. What about birth control interactions?

Ritonavir reduces hormonal contraceptive efficacy. Use alternative contraception during treatment.

Q6. When should I expect symptom improvement?

Most patients report symptom relief within 3 days of starting treatment when initiated early.

Q7. Are there renal dosing adjustments?

Yes – for eGFR 30-60mL/min: 150mg nirmatrelvir + 100mg ritonavir BID
eGFR <30mL/min: Special loading/maintenance dosing required