Amal Clooney's husband revealed his diagnosis on Jimmy Kimmel Live
George Clooney shut down an attempt to poke fun at his teenage appearance as he revealed he suffered from Bell's palsy.
The Ocean's Eleven star featured on a special 20th-anniversary episode of on Thursday and revealed his health condition when he was shown a photo of himself as a 15-year-old high school student.
WATCH: Jimmy Kimmel's awkward reaction to George Clooney's Bell's palsy diagnosis
In the image, George is sporting a half-smile on his face, but the actor cut off Jimmy before he could make a joke about his appearance.
"Now wait, I want to point out something because you're going to laugh, gonna make a joke. I have Bell's palsy there and half of my face is paralyzed," George said.
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"Look at this, watch this. If you go like this," he added as he covered half his face in the photo with his hand. "On the other side, it's a completely different face. So now make your joke.
"Make your funny joke. Come on, funny man. Come on, let me give you sad face."
George suffered from Bell's palsy when he was a teenager (Photo: ABC)
George was just 14 years old when he noticed that something wasn't quite right after he dribbled milk out of his mouth during a post-church lunch.
"I thought, 'Oh, my God, I have Lou Gehrig's disease,'" he told Larry King in 2006.
George is now married to Amal Clooney
However, the dad-of-two was fortunate that his Bell's Palsy lasted about nine months, although that felt like an eternity in high school. He noted: "It was the first year of high school, which was a bad time for having half your face paralyzed."
According to the Mayo Clinic, Bell's palsy is a condition that causes "sudden weakness in the muscles on one side of the face".
In most cases, the weakness is temporary, but it makes "half of the face appear to droop. Smiles are one-sided, and the eye on the affected side resists closing".
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