The celebrity news website reports police told them the 25-year-old was taken to an LA hospital from her Hollywood home but her condition is unknown.
The American singer was reportedly treated with Narcan, an emergency treatment for narcotic overdoses.
Paramedics found her unconscious when they arrived at her home.
The singer, who has struggled with substance abuse for some years, released a song recently called Sober, in which she reveals she had relapsed.
The singer has been open about her addictions and her struggle with bipolar disorder and an eating disorder.
She has spent time in rehab and has admitted self-harming.
The Let It Go singer has worked with charities in the US to raise awareness of mental illness.