Why Is There a Huge Cotton Ball in My Aspirin Bottle?

When you have a headache, every second that stands between you and relief is one second too long. That’s why that giant wad of cotton shoved into many bottles of over-the-counter pain meds is such a, well, pain.

You’ll be happy to know that there’s a reason for all that pill packing material—and even happier to know that it’s a dying trend.

Bayer originally put the cotton there sometime in the early 20th century. Its purpose was simply to fill the rest of the space in the bottle and immobilize the pills, preventing the powdery tablets from jostling around and pulverizing themselves. Which makes perfect sense.

However, by the 1980s, Bayer had embraced the pharmaceutical innovation of coated tablets. It no longer mattered if the pills knocked around in the container, because the coating prevented them from disintegrating; gel caps were also less fragile. But after decades of opening aspirin bottles and finding the fluffy filling, consumers were conditioned to expect it, even believing that it was a good way to tell if the package had been tampered with, or that it helped keep the pills “potent.” Consumer beliefs like these—and tradition—were the main reasons Bayer kept cotton in their bottles for so long, and likely play a part in why some brands still include it today.

In reality, the National Institutes of Health (NIH) recommends removing the cotton, as it can actually pull moisture into the bottle. And the government institution isn’t the only one warning against the wads: in 1983, the late Andy Rooney railed against it on 60 Minutes (in the way that only Andy Rooney could).

But here’s another secret: Not only is the cotton in some bottles totally unnecessary, it probably isn’t even cotton. According to the Drug Information & Side Effects Database, most of the plugs are made from rayon or polyester.

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