It's called the Cinnamon Challenge.
It's become an internet sensation: YouTube video of mostly teenagers trying to swallow a spoonful of cinnamon.
It's a double-dog dare that's gone very viral.
Roughly 30,000 such videos are on YouTube.
But swallowing the spice commonly used for cookies and pies is basically impossible because there's not enough saliva in the human mouth to absorb it.
Doctors warn that creates other dangers.
"It can cause you to gag right away, which then when you expel it, can get in the eyes, cause damage to the eyes, burning to the eyes," says Dr. Andrew Hertz.
And that's not the worst of it.
"It can get into your nose and into your airway, down into your lungs, which will cause you to have more coughing," Dr. Hertz says.
In extreme cases the inflammation and coughing is so severe your lungs could collapse.
That's what happened to Fred Reed's daughter.
"My daughter stayed in the hospital for almost a week and I almost lost her," Reed says.
Doctors say parents should talk to their kids about the potential dangers of the Cinnamon Challenge, because there is nothing sweet about it.
School districts across the country have issued letters to parents informing them of the Cinnamon Challenge, and some have banned students from bringing the spice to school.
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