An immune-modulating compound used to reduce the symptoms of multiple sclerosis and now showing potential against coronaviruses, interferon beta is the last of the WHO's Covid-19 Solidarity trial candidates to get the Chemistry in its element treatment.

The unexplained appearance and dramatic spread of a new form of HIV drug ritonavir hurt patients and cost its makers almost $250 million. Alexander Whiteside on the chemical phenomenon that links Irving Langmuir, H G Wells and Kurt Vonnegut.

Ben Valsler explains how a drug that prevents HIV from donning its protective 'coat' now makes up one arm of the World Health Organisation's Covid-19 trial

Will new clinical trials for Covid-19 give remdesivir a second chance?Ben Valsler introduces the broad-spectrum antiviral that didn't quite make it as the Ebola drug it was originally planned to be.

Old drugs sometimes find their way back into the news. The Covid-19 pandemic – and some very high profile backing – has led to malaria drugs chloroquine and hydroxychloroquine hitting the headlines worldwide. Ben Valsler explores both the history and the hype.

Brian Clegg on the popular over-the-counter painkiller, developed by a high-street pharmacy chain

Catherine Hodges explores the chemical solutions to thinning hair and patchy beards, examining the popularity of minoxidil and the cautionary tale of finasteride

The pesticide that keeps pets free of pests, but may have also been responsible for the devastating collapse of bee colonies. With Harriet Brewerton.

Rotund rodents revolutionised our understanding of the biological role of fat. Now, as Katrina Krämer discovers, the hormones created by fats could redefine obesity.

Ben Valsler on vitamin K – the blood clotting factor that is likely to be the first supplement you ever receive