The Tonight Show host canceled Thursday's taping of the NBC late-night staple—a rarity—after he felt sick and voluntarily opted to go to the hospital.
Leno's spokesman, Dick Guttman, said that the comedian was in his office at NBC's Burbank, Calif., studios at the time and left for nearby Providence St. Joseph Medical Center around midday. He characterized Leno's condition as "mild."
"Jay Leno is doing just fine," NBC spokeswoman Tracy St. Pierre told E! News this afternoon. "He was kidding around with the hospital staff and running his monologue jokes by the doctors and the nurses. He's expected back to work on Monday."