A loophole in FDA processes means older drugs like the ones in oral decongestants weren’t properly tested. Here’s how we learned the most popular one doesn’t work

In 2005, federal law compelled retailers nationwide to move pseudoephedrine, sold as Sudafed, from over-the-counter (OTC) to behind it, so as to combat its use in making illicit methamphetamine. This move changed the formulas of cough and cold medicines in the U.S.. It also led me and my colleague Leslie Hendeles to prove that pseudoephedrine’s replacement, oral phenylephrine, was ineffective as a decongestant.

We petitioned the Food and Drug Administration (FDA) twice, yet it took the agency more than a decade and a half to act on our findings.

In September, an agency advisory panel finally agreed with our conclusion that this compound did little to quell congestion and recommended that products containing it be pulled from shelves. If FDA acts on this recommendation, oral phenylephrine could be the first OTC drug approved under the agency’s “monograph” process to be discontinued. But in the meantime, millions of people have been trusting the FDA’s OTC regulatory process to ensure that medications work, but instead have been wasting money for nearly two decades on ones that don’t.