New easy-to-use Covid-19 pills come with a catch

Newly infected Covid-19 patients have two new treatment options that can be taken at home. But that convenience comes with a catch: The pills have to be taken as soon as possible once symptoms appear.

The challenge is getting tested, getting a prescription and starting the pills in a short window.

US regulators authorised Pfizer’s pill, Paxlovid, and Merck’s molnupiravir last week. In high-risk patients, both were shown to reduce the chances of hospitalisation or death from Covid-19, although Pfizer’s was much more effective.

Who should take the pills?

The antiviral pills aren’t for everyone who gets a positive test. The pills are intended for those with mild or moderate Covid-19 who are more likely to become seriously ill. That includes older people and those with other health conditions like heart disease, cancer or diabetes that make them more vulnerable. Both pills were approved for adults while Paxlovid is authorised for children ages 12 and older.

Who shouldn't take the pills?

Merck’s molnupiravir is not authorised for children because it might interfere with bone growth. It also isn’t recommended for pregnant women because of the potential for birth defects. Pfizer’s pill isn’t recommended for patients with severe kidney or liver problems. It also may not be the best option for some because it may interact with other prescriptions a patient is taking. The antiviral pills aren’t authorised for people hospitalised with Covid-19.

What's the treatment window?

The pills have to be started as soon as possible, within five days of the start of symptoms. Cough, headache, fever, the loss of taste or smell and muscle and body aches are among the more common signs. The Centers for Disease Control and Prevention offers a website to check your symptoms.

Dr. Cameron Wolfe, an infectious disease specialist at Duke University Hospital, advises getting a test as soon as you have symptoms of Covid-19.

“If you wait until you have started to get breathless, you have already to a large extent missed the window where these drugs will be helpful,” Wolfe said.

Do the pills work for Omicron variant?

The pills are expected to be effective against Omicron because they don’t target the spike protein where most of the variant’s worrisome mutations reside. The two pills work in different ways to prevent the virus from reproducing.

Are there options for new Covid patients?

Yes, but they aren’t as easy to use as a pill: They are given by IV or injection, typically at a hospital or clinic. Three drugs provide virus-fighting antibodies, although laboratory testing suggests the two aren’t effective against Omicron. British drugmaker GlaxoSmithKline’s antibody drug appears to work, and officials say they are working to increase the US supply. The only antiviral drug approved in the US, remdesivir, is for people hospitalised with Covid-19.

• Americas