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Common questions about molnupiravir

How does molnupiravir work?

Molnupiravir stops the COVID-19 growing and spreading. It works by preventing the virus from multiplying and keeping virus levels low in your body.

This helps your body's immune system control the infection and reduces the risk of severe symptoms.

How long does it take to work?

Molnupiravir starts to work very quickly after you take it. It works best when it's taken as soon as possible after you've had a positive COVID-19 test and within 5 days of your symptoms starting.

Everyone has a different experience of COVID-19 infection, especially if you have risk factors for getting severe disease.

Most people who take molnupiravir will recover quickly after taking this medicine, with a reduced risk of severe illness.

Are there any long-term side effects?

It's not known if there any long term side effects from taking molnupiravir.

What will happen if I stop taking it?

Do not stop taking molnupiravir before you have finished the 5 day course without talking to your doctor first.

If you stop taking molnupiravir before the end of the course, it may no longer protect you from becoming severely ill from COVID-19.

How does molnupiravir compare with other medicines to treat COVID-19?

Molnupiravir is an antiviral medicine that treats COVID-19.

There are other antiviral medicines for early COVID-19, such as Paxlovid tablets (nirmatrelvir and ritonavir) and remdesivir, a medicine that is given through a drip in your arm (infusion).

If antiviral medicines are not suitable for you, sotrovimab may be offered instead. Sotrovimab is a biological medicine. It is also known as a neutralising monoclonal antibody (nMAb).

COVID-19 treatments do not replace vaccinations. Vaccines are given to help your immune system fight a future COVID-19 infection.

How effective is molnupiravir?

If you have COVID-19, molnupiravir reduces your risk of severe symptoms and needing hospital treatment.

It's important to take molnupiravir within 5 days of the start of your COVID-19 symptoms to give it the best chance of working.

Will it affect my contraception?

If you have COVID-19 it's important you do not have contact with other people to avoid passing the infection on.

Molnupiravir will not stop your contraception working. This includes the combined pill and emergency contraception.

But if it makes you sick (vomit) or have severe diarrhoea for over 24 hours, your contraceptive pills may not protect you from pregnancy. Check the pill packet to find out what to do.

Find out what to do if you're on the pill and you're being sick or have diarrhoea.

Can I drive or ride a bike?

If you're being treated for COVID-19, stay at home to avoid passing the infection on to other people.

Some people feel dizzy while taking molnupiravir. This may make it more difficult to concentrate and react.

If you feel dizzy, do not drive a car, ride a bike, or use tools or machinery.

It's an offence to drive a car if your ability to drive safely is affected. It's your responsibility to decide if it's safe to drive. If you're in any doubt, do not drive.

GOV.UK has more information on the law on drugs and driving.

Can I drink alcohol while taking molnupiravir?

It's not known if alcohol affects molnupiravir. However, if molnupiravir gives you headaches or makes you feel dizzy it's best not to drink alcohol.

Is there any food or drink I need to avoid?

You can eat and drink normally while you are taking molnupiravir.

It's important to drink plenty of fluids to stay hydrated if you're unwell with COVID-19.

Page last reviewed: 21 December 2021
Next review due: 21 December 2024