What Is Lagevrio? Uses, Dosage, and What You Need to Know in 2026

Lagevrio is the brand name for molnupiravir — an oral antiviral medication used to treat COVID-19. Made by Merck Sharp & Dohme in collaboration with Ridgeback Biotherapeutics, it was one of the first oral COVID-19 pills to become available in the United States. Here's what you need to know about it in 2026.

What Is Lagevrio (Molnupiravir)?

Lagevrio (molnupiravir) is a nucleoside analogue antiviral. Unlike Paxlovid, which inhibits a viral protease enzyme, Lagevrio works by introducing errors into the virus's genetic code during replication — a process called viral error catastrophe or lethal mutagenesis. This causes the SARS-CoV-2 virus to produce defective copies until it can no longer replicate.

Lagevrio is taken as a capsule — specifically, four 200 mg capsules twice daily (every 12 hours) for 5 consecutive days, for a total of 40 capsules. It can be taken with or without food. Capsules must be swallowed whole — do not open, break, or crush them.

What Is Lagevrio Used For?

Lagevrio is authorized under FDA Emergency Use Authorization (EUA) for the treatment of mild-to-moderate COVID-19 in adults who:

Have tested positive for SARS-CoV-2 (COVID-19)

Are at high risk for progression to severe COVID-19, including hospitalization or death (e.g., age 65+, obesity, diabetes, heart disease, COPD, immunocompromised status)

Are within 5 days of symptom onset

Cannot use other FDA-authorized COVID treatments (such as Paxlovid or Remdesivir) because they are inaccessible or clinically inappropriate

Importantly, Lagevrio has not received full FDA approval — only Emergency Use Authorization. It is not authorized for pre-exposure or post-exposure prevention of COVID-19, and it should not be used in hospitalized patients (it is not authorized for severe or critical COVID-19).

How Effective Is Lagevrio?

The pivotal MOVe-OUT clinical trial enrolled 1,433 adults with mild-to-moderate COVID-19 at high risk for severe disease. Among patients who received Lagevrio, 6.8% were hospitalized or died within 29 days — compared to 9.7% in the placebo group. This represents approximately a 30% reduction in the risk of hospitalization or death.

While this is a meaningful benefit for patients who need it, Lagevrio is less effective than Paxlovid, which showed approximately 89% risk reduction in its original trial. This is why Lagevrio is prescribed as a second-line option when Paxlovid is not suitable.

Dosage and How to Take Lagevrio

Dose: 800 mg (four 200 mg capsules) every 12 hours for 5 days

Total: 40 capsules per course of treatment

Timing: Start as soon as possible after diagnosis, within 5 days of symptom onset

Food: Can be taken with or without food

Missed dose: If less than 10 hours have passed, take it as soon as you remember. If more than 10 hours, skip and take the next dose at the regular time. Never double-dose.

Who Should NOT Take Lagevrio?

Pregnant patients (or those who could become pregnant without using contraception)

Patients under 18 years of age

Patients who are breastfeeding (or who should pump and discard milk during treatment and 4 days after)

Patients who are hospitalized specifically due to COVID-19 (not authorized in this setting)

Finding Lagevrio in 2026

Lagevrio requires a prescription, and many pharmacies don't routinely stock it. If you have a prescription and need help finding a pharmacy with Lagevrio in stock, medfinder can contact pharmacies near you to check availability and text you the results.

For a deeper dive into how Lagevrio works at the molecular level, see our article on Lagevrio's mechanism of action.