When you’re using eye drops and feel like you’re spilling half of each dose down your face, it’s not because you’re clumsy. You are, in fact, spilling what can be pricey medicine down your cheeks or into your sinuses, because most eye drop bottles dispense at least twice as much as you need.

Why would that be? A ProPublica report explains that liquid medications are sold by volume, and drug companies don’t really have any incentive to help us use them up any more slowly — whether they’re inexpensive over-the-counter moistening drops or a glaucoma medication that costs hundreds of dollars per bottle.

In this case, more medicine isn’t better: Eye drop bottles dispense as much as 50 microliters per dose, when the eye can only hold less than half that amount of liquid.

ProPublica interviewed a chemist who was on the team at Alcon (now part of Novartis) that figured out how to dispense medication in a 16-microliter drop that was just enough medication to coat the eye. A study of glaucoma patients showed that the smaller amount of medication was effective.

The research was published 25 years ago, which means that pharmaceutical companies have had plenty of time to change their bottles and reduce waste.

Alcon didn’t want to take the risks needed to get its microdrops on the market. A different dosage of eye medication would need its own approval from the Food and Drug Administration, requiring more studies to prove that the smaller dose is just as effective. It would also reduce sales, putting the company at a competitive disadvantage if it had to raise the price of products dispensed in microdrops.

“[Drug companies] had no interest in people, their pocketbooks or what the cost of drugs meant,” one ophthalmologist told ProPublica, explaining what happened when he has asked drug companies why they can’t make drops less wasteful.

Remember that the next time your eye drops run down your face: Millions of dollars are wasted every year because no pharmaceutical company wants to be the first to make this change.

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