"A repeat of 'The Tonight Show with Jay Leno' will air tonight as Mr. Leno is not feeling well," a rep for the show told Access Hollywood.
"He took himself to the hospital because he wasn't feeling well," the rep added.
Leno rarely gets sick. Rumors have surfaced the funnyman may be suffering from food poisoning, however that has not been confirmed.
Big Bad Voodoo Daddy wrapped up their sound check just around noon, with their singer doing a spot-on impression of a Jay Leno-style introduction.
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