Justin Bieber has shared his shock at learning of Demi Lovato’s drug overdose.

“It’s very sad,” Justin told TMZ. “No I haven’t talked to her, but my prayers go out to her and her family for sure. I thought she was sober, that’s terrible, right?”

It appears Bieber might not have heard Demi’s latest single, Sober, in which she confesses to no longer being sober after six years off alcohol and drugs.

In it, she sings:

“Mumma I’m so sorry I’m not sober anymore / And Daddy please forgive me for the drinks spilled on the floor. To the ones who never left me, we’ve been down this road before / I’m so sorry, I’m not sober anymore.”

Yesterday, a spokesperson for the 25-year-old said she was awake and recovering in hospital after suffering a drug overdose. It was not confirmed which drug Demi had taken, but the statement said some information that’s been reported is not correct.

At around lunchtime on Tuesday in Los Angeles, an ambulance was called to Demi’s Hollywood Hills home with reports a woman had overdosed.

The Sorry Not Sorry singer has been open about her battles with substance abuse.

thoughts?