Twenty years ago, scientists found that phenylephrine, listed as a decongestant in many cold medicines, didn’t work. What can you use instead? In September, an advisory committee for the Food and Drug Administration unanimously confirmed that phenylephrine—a common ingredient in cold medicines, including some types of Mucinex and Robitussin—doesn’t work.For many physicians, pharmacists, and cold-sufferers, this came as no surprise. Phenylephrine’s ineffectiveness had been an open secret in the healthcare community for decades.In 2005, Dr. Randy Hatton, clinical professor at the Pharmaceutical Outcomes and Policy Department at the University of Florida, managed the University of Florida Drug Information and Pharmacy Resource Center hotline. He often received calls from pharmacists reporting that phenylephrine-based drugs had no effect on improving colds.He came across research from Dr. Leslie Hendeles, professor emeritus of the College of Pharmacy, also at the University of Florida, from a decade prior. Dr. Hendeles had also found that the substance was ineffective. They partnered up and petitioned the FDA to publicly confirm their finding. Their collaboration was the first step toward the FDA’s recent announcement.But despite the announcement, the removal of these drugs from shelves is not guaranteed. Pharmaceutical companies are appealing the FDA’s decision, and are trying to stall an official declaration that prohibits their sale.Guest host Flora Lichtman talks with Dr. Hatton and Dr. Hendeles about the long road to the FDA’s announcement.They discuss how their research proved phenylephrine’s ineffectiveness, and which drugs people can turn to instead as cold season approaches.To stay updated on all things science, sign up for Science Friday's newsletters. Transcripts for each segment will be available the week after the show airs on sciencefriday.com. Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.