Demi Moore was doing "whip-its" -- a type of nitrous oxide inhalant -- before she was rushed to the hospital earlier this week, TMZ reported.
The troubled actress became semi-conscious and had symptoms of a seizure after inhaling a dangerous amount of nitrous oxide -- a gas typically inhaled by young people looking for a cheap high -- a friend told paramedics who attended the scene, the gossip site reported.
The 49 year old was rushed to the hospital from her home in Los Angeles late Monday night, before checking into a treatment facility Tuesday to reportedly seek treatment for substance abuse.
Her rep said that she was seeking "professional assistance to treat her exhaustion and improve her overall health."
However friends of the star said she went to rehab because she is "emotionally and physically exhausted" over her painful split with Ashton Kutcher, who is "acting like a teenage boy," the New York Post reported.
One friend told the newspaper that Kutcher, 33, who was spotted partying with Brazilian supermodels Monday at Sao Paulo fashion week, continues to flirt with women while still calling his ex "when he is at a low moment."
"Demi was talking to Kobe Bryant at a CAA Golden Globes party, and Ashton came over and made a scene," the source told the newspaper. "He made jealous comments to Kobe, then Ashton went to the bar and was openly flirting with other women."
"Demi put up with a lot from Ashton -- and despite the rumors, she always gave him the benefit of the doubt." the source continued. "Now he's carrying on like a teenager, goes around with other women, and then, when he's feeling scared and lonely, he reaches out to Demi."
The friend said Kutcher's behavior was taking its toll on the star, who has pulled out of her latest movie "Lovelace," adding that Moore felt "exhausted and humiliated."
Moore announced she was ending her marriage to Kutcher after six years -- amid reports he had engaged in multiple extramarital affairs.