If you have kids, sifting through countless parenting books and websites to find just the right advice can seem like an endless task. While we can’t tell you the best way to raise the perfect young lady or gentleman, we can offer up some child-rearing tips from the 1800s that you should definitely avoid—like soothing a crying baby with opium.

In the 19th century, it was common practice to quiet a fussy or sick child with "medicines" like Stickney & Poor’s Paregoric Syrup—a substance that not only contained more than a tenth of a gram of opium per ounce, but that was almost 50 percent alcohol! No wonder it was able to deliver on its promise of calming children down. Unfortunately, this wasn’t the only toxic remedy that parents embraced in the days of yore: Kids were regularly made to ingest turpentine in order to rid themselves of tapeworms, while mercury was believed to be a cure for dysentery or edema.

In this edition of The List Show, Mental Floss editor-in-chief Erin McCarthy dives into the many toxic substances that were administered to children, plus the history of baby cages, gum lancing, and many more puzzling child-rearing practices from the 1800s. You can watch the full episode below.

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