The World Health Organization notes 300 essential drugs are now in shortage. Chris Baraniuk asks what is behind the problems and what countries are doing about it It wasn’t long after Katie Suda ordered her chronic pain medication that she got an unexpected text message. It said that the drug she needed was out of stock. “It was stressful,” she recalls. But Suda is an unusual kind of patient; she happens to be a professor of medicine at the University of Pittsburgh—and her research focuses on drug shortages. “I looked in our database and I found that my drug had a supply chain problem,” she says. She spoke to staff at her local pharmacy. “Luckily, they were able to get the drug in from a different supplier—but that’s not the case for every patient or every condition.” Reports1 suggest that in recent years more and more people around the world2 have found it difficult to access the drugs they need. Part of this is because of disruption caused by the covid-19 pandemic, but the problem is