The pop star's mother, Dianna De La Garza, and 16-year-old sister, Madison De La Garza, were seen arriving at the hospital and a large security presence has also gathered outside, E! News reports. Demi's aunty tweeted that she is "stable and alert."
TMZ says paramedics found the singer unconscious at her Hollywood Hills home after being called there around noon (USA time) on Tuesday.
Police confirmed to The Hollywood Reporter that they were called to a home on Lovato's block for a suspected overdose, but refused to confirm anything further.
Demi recently released a song, revealing she had suffered a relapse. In the music, titled 'Sober,' she sang: "Momma, I'm so sorry, I'm not sober anymore" and told fans, "sorry that I'm here again".
Lovato had previously been sober for six years.
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