The pop artist was scheduled to perform in the latest show of "In Performance at the White House." Usher and The Band Perry were also expected to play.
Lovato also launched a new music video on Wednesday for the song "Stone Cold" from her latest album Confident.
The intensely sad video captures Lovato soaking in a bathtub after crying atop a cold, white mountain.
In an Instagram post, the singer explained the meaning behind the video.
"This song hurts. So unbelievably bad. And when I perform it on a TV show, in rehearsals or even in a bathtub, it completely takes me to a different place. This song was so therapeutic to write and record, and because of that I wanted to translate that same emotion onto the screen."
Copyright 2016 United Press International, Inc. (UPI). Any reproduction, republication, redistribution and/or modification of any UPI content is expressly prohibited without UPI's prior written consent.