The death of Anna Nicole Smith was officially ruled an accident yesterday after tests revealed that the former Playmate of the Year had nine legal drugs in her blood — including a potent sleeping medication.

The coroner in Florida, where the former stripper was found unresponsive at a luxury hotel on February 8, ruled out murder or suicide, even though there was evidence that she had been depressed.

The ruling ended weeks of speculation over the role of her lawyer and boyfriend, Howard Stern, who is one of several men who claim to be the father of her newborn daughter, Dannielynn. The child has been dubbed the “billion-dollar baby” because she stands to inherit a fortune from Ms Smith’s late husband, the Texas oilman J. Howard Marshall II.

Charlie Tiger, the local police chief, said the investigation of Ms Smith’s death was now closed. “We are convinced, based on a thorough review of the evidence, that this has been an accidental overdose with no other criminal element present,” he said.

Dr Joshua Perper, the Broward County medical examiner, said a sedative called chloral hydrate had “tipped the balance” when added to the other drugs. “The chloral hydrate was taken as a syrup. There was about a quarter of a glass. The normal dose is about one to two teaspoons. She normally took much more, like two tablespoons. In this case, she exceeded that dose,” he said.

Dr Perper confirmed that Ms Smith, 39, suffered from depression after her 20-year-old son Daniel died of a drug overdose days after she gave birth to Dannielynn in September. She voiced suicidal thoughts at that time, but an incident in which she almost drowned in a swimming pool appears to have been the accidental result of drug use, he said.

Analysis of her computers showed that she had largely recovered from her depression and was in “good spirits.” Toxicology tests revealed that Ms Smith had used methadone, the painkiller that killed her son, days before she died. But the coroner said it played no role in her death because it was no longer present in her blood.

Tests found nine other medications in her blood, including Valium, Tylenol, weight-loss drugs, vitamin B-12, over-the-counter antiflu tablets, antibiotics and human growth hormone. “She had a history of multiple prescription drug use and overmedication in the past,” Dr Perper said.

The coroner said Ms Smith got a 105-degree fever from an infection caused by an injection of antiageing growth hormone that perforated an abcess in her buttock. He did not know who had administered the injection, but that it did not cause her death.

Ms Smith flew to Florida from the Bahamas with Mr Stern on February 5 and complained of pain and chills. She was prescribed antibiotics and antiflu medicine and given an ice-bath that brought her temperature down to 97 degrees.

Dr Perper suggested that Miss Smith might have been saved if she had heeded her companion’s advice to go to hospital when she was diagnosed with a high fever, but he added: “In my opinion, she was a very strong kind of woman and she was the one in command. If the boss is telling you ‘I do not want. . .’ you do not question the boss many times.”

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