“At first it was an outlet for my frustration,” says Melvin, whose symptoms eventually led him to an early retirement. “I was unprepared for the amount of people contacting me daily.”

But his own research had led him to strongly suspect fluoroquinolones. He started a blog about his experiences in 2009.

He saw two neurologists, a rheumatologist, and then specialists at the University of Chicago before he learned that he had suffered nerve damage, though his doctors could not find a cause.

Research from personal experience

Among those contacts were a handful of researchers interested in the effects of fluoroquinolones, some of whom had had their own experiences with the drugs. Together, they began to pursue a link between fluoroquinolones and the family of side effects that they seemed to trigger.

“One of our struggles has been to get the acknowledgement that this happens,” Melvin says.

In 2015, the FDA reviewed reports of previously healthy people who had disabling side effects after taking fluoroquinolones for garden-variety sinus infections, urinary tract infections, and bronchitis. Out of 1,122 such cases, the agency found 178 people, or 16%, who had had at least two different types of side effects, including heart and central nervous system problems, that lasted at least a month and as long as 9 years. The FDA dubbed this condition fluoroquinolone-associated disability, or FQAD.

However, the report’s authors acknowledge that the system for reporting side effects does not catch all cases, so the number of people with devastating side effects is likely much higher. One estimate suggests that no more than 10% of all serious side effects get reported.

Overall, the number of people who reported serious side effects from the 1980s through 2015 exceeds 60,000, and that number includes more than 6,500 deaths, according to a recent study.

In its December warning, the FDA said certain conditions made people taking fluoroquinolones twice as likely to have an aortic dissection, or rupture. The agency advised against prescribing such antibiotics to the elderly as well as to people with high blood pressure, peripheral artery disease, or genetic conditions like Marfan syndrome and Ehlers-Danlos syndrome.

But the list of people who should not take them is longer than that, Crespo says. People on kidney dialysis as well as those with diabetes should avoid fluoroquinolones. Fluoroquinolones also should not be taken by people currently on steroids or medications that treat arrhythmia. And because some fluoroquinolones also have been linked to liver damage, people with liver problems should not take them.