“When you put it on the inside of your ear and move it around, it feels nice, it becomes a sensual thing. You become like a drug addict, a cigarette smoker,” said Dr. Vito Forte, a professor of otolaryngology at the University of Toronto, who runs the company OtoSim, which makes ear-exam simulators.

Your ear canal is a tube closed off at one end by your eardrum. When you chew and talk, that helps move wax out towards the opening so it doesn’t impede hearing. Inserting a Q-tip or a screwdriver actually reverses that motion, pushing wax back where you don’t want it to be, sometimes creating hardened balls of wax. Then it becomes a job for an otolaryngologist, who might use a tiny suction-tip or beak-like forceps to pull it out.

The tools involved might be minuscule, but the impact isn’t: In 2012, the Medicare program paid nearly $47 million for over a million removals of earwax balls. Not all of those blockages were caused by rogue ear-cleaners — but their picking and scratching is certainly part of the problem.