Lagevrio

Legal status and availability in the UK

Lagevrio (molnupiravir) is a prescription-only medicine (POM) in the UK.

In our online pharmacy, Lagevrio is available without a prescription, with discreet delivery to the United Kingdom in 9–21 days.

Basic Lagevrio information

• INN (international nonproprietary name): Molnupiravir
• Brand names available in the United Kingdom: Lagevrio™ (MSD), 200 mg capsules, usually provided in 5‑day packs of 40 capsules
• ATC code: J05AB18
• Forms and dosages: 200 mg oral capsules; standard regimen is 4 capsules twice daily for 5 days
• Manufacturers in the United Kingdom: Merck Sharp & Dohme (MSD), developed with Ridgeback Biotherapeutics
• Registration status in the United Kingdom: Conditional marketing authorisation (MHRA) for adults with mild-to-moderate COVID-19 at increased risk of progression
• OTC / Rx classification: Prescription-only medicine (POM)

Product basics and formulation

INN, brand name and manufacturer

What exactly is this medicine and who makes it?

The international nonproprietary name (INN) is molnupiravir.

The trade name Lagevrio™ is used by Merck & Co. (MSD).

The ATC classification is J05AB18 (direct-acting antiviral).

Indications, authorised use and limits

Who it’s for and who it isn’t for

Who should be offered molnupiravir and who must not receive it?

Molnupiravir is authorised for treating mild‑to‑moderate COVID‑19 in adults at increased risk of progression to severe disease, when started within five days of symptom onset.

It is not authorised for prevention, for use in hospitalised patients, or for severe or critical COVID‑19.

In the UK it is authorised by the MHRA, and national guidance determines which patients are eligible for treatment.

• Authorised use: Early outpatient treatment of high‑risk adults with mild‑to‑moderate COVID‑19, start within five days.
• Not authorised: Prophylaxis, hospitalised severe/critical COVID‑19, patients under 18 years.

Dosage and administration (practical)

Standard regimen, timing and example schedule

How should patients take lagevrio so it gives the best chance of benefit?

The standard adult dose is 800mg taken twice daily for five days, which equates to four 200mg capsules every 12 hours and a total of 40 capsules per course.

Therapy should begin within five days of symptom onset for authorised use.

Patients must be told to complete the full five‑day course even if symptoms improve.

Do not extend therapy beyond five days as safety and efficacy beyond that period are not established.

Missed‑dose guidance: take the missed dose as soon as remembered unless the next dose is due soon; do not double doses to catch up.

In case of overdose, manage symptomatically; there is no specific antidote.

• Sample dosing schedule: Day 1–5 — 4 capsules every 12 hours (e.g. 08:00 and 20:00).
• Quick reference: 800mg (4 × 200mg) twice daily for 5 days; start within 5 days of symptoms.

Contraindications and special‑population rules

Absolute and relative contraindications

Which patients must not be given molnupiravir and where should extra caution apply?

Absolute contraindications include pregnancy, age under 18 years, known hypersensitivity to molnupiravir or any excipients, and use for hospitalised COVID‑19 patients.

Relative cautions include breastfeeding, severe hepatic or renal impairment where data are limited, immunocompromised patients who require close monitoring, and complex polypharmacy situations.

Women of childbearing potential should receive contraception advice in line with local recommendations and pregnancy testing where appropriate before initiation.

• Absolute contraindications: Pregnancy; age <18 years; known allergy; hospitalised severe/critical COVID‑19.
• Relative cautions: Breastfeeding, severe hepatic/renal impairment (limited data), immunocompromised patients.

Interactions and co‑prescribing considerations

Drug interactions and comparison with alternatives

Will molnupiravir interact with the patient’s other medicines?

Molnupiravir generally has a low predicted potential for pharmacokinetic drug–drug interactions because it is not a strong cytochrome P450 inhibitor or inducer.

Real‑world interaction data remain limited, so prescribers and pharmacists must still review a patient’s concomitant medicines before supply.

High‑risk scenarios to flag include potent immunosuppressants, drugs with narrow therapeutic indices and medicines where interaction data are scarce.

Compared with Paxlovid (nirmatrelvir/ritonavir), molnupiravir carries a substantially lower interaction burden and can be an option when Paxlovid is contraindicated due to CYP3A interactions.

• Top interaction check points: review anticoagulants, antiarrhythmics, immunosuppressants, antiepileptics, drugs with narrow therapeutic ranges and any recent oncology therapy.
• Action: perform a full medication review and consult the prescriber if in doubt; document any clinical judgement.

Safety profile and adverse effects

Common, less common and serious reactions

What side effects should patients expect and when should they seek help?

Most frequently reported adverse events include diarrhoea, nausea, headache and dizziness.

Less common reactions reported are rash, abdominal pain and fatigue.

No major new safety signals were identified in clinical trials, but ongoing pharmacovigilance continues to refine the safety profile.

Advise patients to stop the medicine and seek urgent care for signs of allergic reaction such as itching, facial swelling or breathing difficulties.

Report suspected side effects through the MHRA Yellow Card scheme.

• Common (≥1–10%): Diarrhoea; nausea; headache; dizziness.
• Less common / serious (rare): Rash; abdominal pain; fatigue; hypersensitivity reactions.

Pregnancy, fertility and breastfeeding guidance

Contraception, pregnancy testing and lactation advice

Can people who are pregnant or breastfeeding take molnupiravir?

Molnupiravir is contraindicated in pregnancy due to animal data indicating potential embryotoxicity.

Women of childbearing potential should use effective contraception during treatment and for the period recommended by national guidance after dosing; pregnancy testing and counselling are advised where relevant.

Breastfeeding is not recommended while taking molnupiravir because data on infant exposure are lacking.

For men, data on reproductive toxicity are limited and up‑to‑date local recommendations on contraception should be followed.

• Quick Q&A: If pregnant — do not take; if breastfeeding — avoid unless clinician advises benefit outweighs risk; contraception — use effective methods per local guidance.

Storage and handling

How should the product be stored?

Store at controlled room temperature between 20–25°C with permitted excursions to 15–30°C, and protect from moisture.

Keep in the original packaging until use and do not freeze.

Check the packaging, expiry date and batch number, and store the capsules securely away from children and pets.

• Storage quick checklist: 20–25°C preferred; avoid moisture; keep original packaging; avoid freezing.

Alternatives to molnupiravir

Paxlovid, remdesivir and monoclonal antibodies

When might molnupiravir be chosen over other COVID‑19 therapies?

Paxlovid (nirmatrelvir/ritonavir) is often first‑line in many guidelines but its use is limited by significant CYP3A drug–drug interactions.

Remdesivir is an intravenous agent principally used in hospital settings, and monoclonal antibodies such as sotrovimab depend on variant sensitivity and availability.

Molnupiravir is an oral option with a lower interaction burden and may be used when Paxlovid is unsuitable or unavailable.

Practical counselling points

What to tell patients, follow‑up and disposal

Start treatment within five days of symptom onset and take four 200mg capsules twice daily for five days.

Complete the full course even if feeling better and do not extend beyond five days.

Avoid pregnancy and breastfeeding while on treatment and seek immediate advice if pregnancy is suspected.

Advise patients to seek urgent care if breathlessness, persistent chest pain or rapid deterioration occurs and to notify their GP or hospital of treatment.

Unused or leftover capsules should be returned to a pharmacy for safe disposal rather than flushed down the sink or thrown in household waste.

• Counselling checklist: start within 5 days; dosing schedule; contraception advice; side‑effect warnings; Yellow Card reporting details.
• Follow‑up: update GP or local record and advise on urgent warning signs.

Delivery across the United Kingdom