According to a hospital spokesman Kris Carraway-Bowman, Locklear was released from Los Robles Hospital & Medical Center in Thousand Oaks at about 5 p.m. She left with her family and was in good spirits, the spokesman said.
The Ventura County Sheriff's Department confirmed to Eyewitness News that they responded to a 911 call made from Locklear's gated home at about 2:30 p.m. Thursday. Hospital officials said moving patients to the intensive care unit from the emergency department is standard protocol.
According to celebrity gossip website TMZ, Locklear's older sister made the call because she was afraid the actress was going to harm herself.
Under the Health Insurance Portability and Accountability Act privacy rule, hospital officials are not permitted without consent of the patient or a family member to say why Locklear was brought to the hospital. TMZ reported it was a dangerous mix of prescription drugs and alcohol that landed her in the emergency room. The hospital has not confirmed this information.
Officials say the actress is now out of danger.
"She is medically stable. Her mom and dad are with her, and they want me to share with her fans that she is in no danger whatsoever, and that she's going to be just fine," Carraway-Bowman said.
Drug addiction expert Cary Quashen says prescription drugs are drugs of opportunity because you can easily get them from a doctor.
"Prescription drugs in itself are dangerous, but mixing prescription drugs with alcohol is a recipe for disaster. I mean, it's a deadly combination, and it even says that on prescription bottles, 'do not mix with alcohol,'" said Quashen with Action Family Counseling Drug and Alcohol Treatment.
In 2009, Locklear evaded DUI charges by pleading no contest to a misdemeanor reckless driving charge. Tests revealed no alcohol in her system after her arrest, but prosecutors charged her with driving under the influence of prescription drugs. She was sentenced to serve three years informal probation and was fined $700.
"If in fact Heather was brought to the hospital due to alcohol and drugs, there really needs to be a life change here. She really needs to get into some kind of treatment. Walking into the hospital and getting detoxed is not enough," said Quashen.
Locklear, 50, was seen just this week taking in a Lakers game with a friend and actor Woody Harrelson.
Her sharp tongue and striking looks have made her one of television's favorite vixens, but the unflappable characters she plays on the screen may be far from the real-life star, who is reportedly going through a rough time personally after her split with actor Jack Wagner.
The two met on the set of the hit 1990s drama series "Melrose Place," and the on-screen romance turned into a real-life romance, until Locklear called off their engagement last November.
The actress was previously married to Bon Jovi guitarist Richie Sambora and have a daughter together.
The Associated Press contributed to this report.