Demi Lovato was hospitalized Tuesday morning for an alleged heroin overdose, according to TMZ. Lovato is in “stable” condition, an unnamed source tells Variety.

A spokesperson for the Los Angeles Fire Department confirmed to Rolling Stone that it responded to a medical emergency call at 11:22 a.m. from a Hollywood Hills residence in the 8000 block of Laurel View Drive, where Lovato lives. The LAFD transported a 25-year-old female patient to a local hospital.

The Los Angeles Police Department confirmed that a police vehicle was also dispatched after the emergency call, but there was no criminal activity at the location.

Lovato’s representatives did not respond to a request for comment.

The “Sorry Not Sorry” singer has been transparent about her struggles with eating disorders and alcohol and cocaine addictions. Last October, those battles were the focus of an intimate documentary, Simply Complicated.

At the time, Lovato spoke to Rolling Stone about being honest with her fans and learning to live with bipolar disorder. “If anything, I’m proud to be bipolar and speak about it. Bipolar is a mood disorder. I deal with mood swings, I deal with episodes of mania, and bipolar-depression phases as well. But I’ve used my voice to help others, and I feel proud that I’ve been able to do that.”

In March, Lovato announced on Twitter that she was officially sober for six years. “So grateful for another year of joy, health and happiness,” she wrote. “It IS possible.”

Just months later, in June, she released the heartfelt ballad, “Sober,” about a person who suffers a relapse. Lovato became emotional performing the song for the first time live during Rock in Rio. The lyrics, in part, read as an apology to disappointed fans: “And I’m sorry for the fans I lost/ Who watched me fall again/ I wanna be a role model/ But I’m only human.”