FOR OVER 20 YEARS, LINDA BUONANNO lived in fear that her irritable bowel syndrome (IBS) would suddenly interrupt her daily routine with frequent trips to the bathroom and unbearable cramping. Buonanno, now a 71-year-old medical assistant and hairdresser from Methuen, Mass., tried everything from drugs to dairy-free diets. Nothing worked. She remembers a particularly tough period over 10 years ago, when she was working on the factory floor of a medical-device company for up to 10 hours a day, six days a week. When an IBS episode would strike, her coworkers would cover for her as she huddled in a corner, keeled over in pain. If she wanted to go dancing with friends at the local club on Sunday, Buonanno would stop eating on Friday so there wouldn’t be anything in her system to interrupt her plans. “It was a horrible way to live,” she says. One day in 2009, she saw a TV ad looking for people with IBS to enroll in a study. She signed up and was thrilled when she was among about 80 people selected to take part in a first-of-its-kind clinical trial. But when she found out what kind of treatment she’d be receiving, Buonanno felt deflated: a placebo pill. The doctors told her there were no active ingredients in the pills, and the word PLACEBO was labeled clearly on the bottle. She felt she’d gotten her hopes up for nothing.
Three weeks later, after taking the pill twice daily, Buonann