How do Covid antiviral pills work?

Available for over a year

So far hospitals have been using medication for other diseases to ease Covid symptoms. Now two new antiviral drugs have been developed specifically for Covid. The UK is the first country in the world to approve a pill from Merck, called Molnupiravir and Pfizer have just announced their new antiviral, called Paxlovid. Pharmaceutical expert Prof Penny Ward from Kings College London explains how they work, starting with Paxlovid - a type of drug known as a protease inhibitor. (Image: A hand holding pills, Credit: Thana Prasongsin/Getty Images.)