Heather Locklear is a "different person" when she is intoxicated.
The 50-year-old actress was taken to hospital yesterday afternoon after taking a reported concoction of prescription drugs and alcohol.
It is thought that Heather's sister phoned emergency services as she was concerned the actress might hurt herself.
"Heather became a different person on drugs," a source told ET Online. "She was out of control."
Heather's parents have faith that their daughter will recover well following her stay in hospital. She is currently in medically stable condition.
"She is in no danger and she's going to be just fine," her mother and father Bill and Diane Locklear said in a statement issued by Los Robles Hospital & Medical Center.
The source revealed that Heather has been in and out of rehabilitation centres for years. Heather is in discussions to go directly from hospital to a rehab facility, but this has not yet been confirmed.
It's understood Heather has been struggling to cope since her engagement to Jack Wagner was called off last year.
The actress has suffered personal problems in the past. In 2008 it was claimed she'd tried to commit suicide, although the allegation was later denied. She was helped for anxiety and depression issues later that year.