Citing law enforcement officials, TMZ reported on Tuesday that pop singer Demi Lovato, 25, has been rushed to a Los Angeles hospital from her home in Hollywood Hills.
According to TMZ's report, a drug overdose may be to blame, but authorities have not confirmed. Her condition is unknown.
Lovato celebrated six years of sobriety in a Twitter post in March.
"Just officially turned 6 years sober. So grateful for another year of joy, health and happiness. It IS possible," Lovato tweeted.
But just months later, Lovato released "Sober" as a single, opening up about her personal battle with substance abuse. In the opening chorus of the song released in June, Lovato sings, "Mommy, I'm so sorry I'm not sober anymore, and daddy please forgive me for the drinks spilled on the floor."