Anna Nicole Smith's death was due to an accidental overdose of a sleeping medication and at least eight other prescription drugs, authorities said Monday.
"We are convinced this was an accidental overdose," Florida's Seminole Police Chief Charlie Tiger said.
Tiger added that there was no evidence that illegal drugs were involved in the former Playboy Playmate's death, and there was nothing found on the computer of Smith's companion, Howard K. Stern, or anywhere else to suggest a crime was committed.
"We found nothing to indicate any foul play," Tiger said.
Dr. Joshua Perper, the medical examiner for Broward County, Fla., said the cause of death was "combined drug intoxication" with the sleeping medication chloral hydrate as the major factor in combination with therapeutic levels of other drugs.
Chloral hydrate is a sedative used to treat insomnia and alcohol withdrawal, relieve anxiety and ease post-surgery pain.
Smith was taking a lengthy list of other medications, including methadone for pain, Valium, anti-anxiety and anti-depression drugs. She had also recently taken longevity medications, B12 and growth hormone, which are used for weight loss.
A viral flu and a bacterial infection from injecting drugs into her buttocks were contributory causes in her death.
Some of the medications Smith was taking were prescribed to her, some to other aliases she used or to other people, but all of the drugs she was on were intended for her, Perper said.
"Miss Smith had a long history of prescription drug use and over-self medicating. She may have drank a little too much chloral hydrate to alleviate symptoms which were secondary to infection," the medical examiner's report said.
The report, while ruling Smith's death accidental, notes that her idol, Marilyn Monroe, died of chloral hydrate and barbiturates.
Dr. Chip Walls, a forensic toxicologist for the Miller School of Medicine at the University of Miami, said chloral hydrate is rarely prescribed and is known to be fatal if combined with certain other drugs -- including the sedative Lorazepam, which the autopsy showed she was taking.
"It's very toxic if you mix it with any other central nervous system depressant drugs," Walls said. "You could get profound sedation leading up to coma and respiratory arrest."
The former reality star had suffered from depression after the loss of her 20-year-old son Daniel in September, but she was starting to feel better and there was no evidence of suicide, Perper said.
"There was no suicide note," the medical examiner said. "She was in good spirits."
Smith also suffered stress from the various lawsuits she was involved in, he added.
Perper had delayed releasing Smith's autopsy results because of additional evidence he was given about what had left the model unresponsive Feb. 8 at the Seminole Hard Rock Hotel & Casino in Hollywood, Fla.
The evidence was information pertaining to two laptop computers belonging to Smith and Stern, Perper said Monday, adding that he was asked at that time not to disclose why he delayed releasing her cause of death, which he felt was justified because there was no criminal investigation under way.
Smith had arrived at the Hard Rock on Feb. 5 and planned to leave four days later aboard a new yacht that Stern was arranging to buy. She was seldom seen outside her room during her stay, and was suffering from a stomach flu before she died.
An assistant medical examiner's report described seeing a table in Smith's hotel room containing cold medicine, sodas cans, SlimFast, nicotine gum and an open box of Tamiflu tablets.
Perper said Smith's sudden spike in fever a few days before she died to an alarming 105 degrees was likely a symptom of the infection caused by an injection of a weight-loss drug into her left buttock. At that time, those with Smith urged her to go to the emergency room, but she flatly refused, he said.
Because her death was so sudden, because her son died under suspicious circumstances five months earlier and because Smith could have had millions coming to her from her wealthy late husband, whose estate she had been fighting for the rights to an inheritance, there had been speculation about possible foul play in both cases.
Perper said he knew of no criminal investigation into Smith's death. The Seminole Police Department investigated the case because the casino is on tribal land.
"We did not find any evidence which would point to homicide," Perper said.
An inquest into Daniel's death is scheduled to start Tuesday in the Bahamas, where he died.
Smith, 39, grew up in Texas and went from topless dancer to Playboy Playmate of the Year, Guess jeans model and bride of 89-year-old oilman J. Howard Marshall II.
She took her fight for Marshall's estimated $500 million fortune as far as the Supreme Court, and the ongoing battle could make her infant daughter, Dannielynn, very wealthy. Stern and two other men have claimed to be the baby's father.