News reports the 77-year-old game show host underwent brain surgery to remove blood clots on December 16 at Los Angeles' Cedars-Sinai Medical Center and is now recuperating.
Trebek said he is taking medical leave after undergoing surgery to remove a subdural hematoma that formed after he fell and hit his head in October.
After spending two days in the hospital, he returned home and is recuperating.
Trebek underwent surgery at Cedars-Sinai Medical Center in Los Angeles on December 16.
Trebek says in the video, "I expect to be back in the studio taping more 'Jeopardy!' programs very, very soon".
Trebek has been the host of Jeopardy! since 1984, and is contracted to host until 2020.
Alex Trebek has a "slight medical problem", in his words-but it's serious enough that Jeopardy! is now on hiatus.
Trebek has never missed taping an episode in all these years, and was only replaced once: when he and "Wheel of Fortune" host Pat Sajak switched places on April 1, 1997. But he assured fans he'd be back reading clues to contestants soon.