I DIDN’T NEED A HIGH-TECH LABORATORY or millions of dollars for R&D. My eureka moment came when I was 12.

I merely had the idea: an automatic pill dispenser. It was my father who executed it in his workshop one afternoon. The device was a simple prototype involving a lamp timer, a piece of copper tubing and a roll of peppermint LifeSavers.

My invention was born of two necessities: to fulfill a seventh-grade science project and to help keep my then 87-year-old grandmother, heading into senility, from taking too many pills at once

Having earned praise in Mrs. Sternfeld’s class, several classmates and I were shipped off to demonstrate our ideas at the 1991 Inventors Weekend at the Museum of Science in Boston. A month later, I was bewildered to get a call from a talent scout at Late Night With David Letterman, who was putting together a kid-inventor segment.

Thus I found myself two days later under the glare of Late Night’s studio lights, shaking Dave’s hand. There I was, in cringe-worthy adolescent glory—replete with bulky, candy-apple-red glasses, a mouth full of braces with colored elastics, a pink headband holding back a mass of unruly hair, a flowery jumpsuit and white sneakers.

“So how many pills is Grandma takin’?” asked Dave.

“We’re really not sure,” I intimated. Dave and the audience roared. So too did my grandmother, my parents told me later. The clip even made it onto Dave’s 10th-anniversary show at Radio City Music Hall.

After our appearance, a fellow inventor (of dust booties) and I were photographed at my house forWoman’s World.

A medical manufacturer sent me a few prototypes of its pill dispenser, a not-so-subtle hint that the market was already cornered. I had no intention of pursuing a patent, anyway. It was too much work; the taste of fame had been reward enough.

Fifteen years later, the term “automatic pill dispenser” yields hundreds of Google hits—but I’m surprised that they haven’t caught on in a bigger way by now. Not because mine was a genius idea (it wasn’t), but because, just as our population is getting grayer and living longer, the average number of pill bottles the elderly tote home from the pharmacy each year is also climbing. As many as 59% of people on five or more medications are taking them improperly (regardless of age), and 10% of hospital admissions for the elderly result from prescription misuse. Those days-of-the-week pillboxes, ubiquitous at drugstores, can’t guard against forgetfulness; to my grandmother, it might have been Monday one minute, Thursday the next. And taking the wrong day’s pills at the wrong time could only make her memory foggier.