It was apparently a bad case of food poisoning that had him so ill.
But Leno's luck didn't get any better this weekend!
On Sunday, on the way to make an appearance at a comedy club, Leno's antique car broke down on the 405 Freeway!
The funnyman was heading southbound and had to pull over to check out the car's engine.
Thankfully, he was able to fix the problem himself.
And, on a better note, it's good to see he's out of the hospital and seems to be doing pretty well.
He's already back to work!
[Image via National Photo Group.]