Suffering from seizures and headaches, he was immediately rushed to Hong Kong Baptist Hospital where doctors diagnosed cerebral edema.
They were able to reduce the swelling through the administration of mannitol.
These same symptoms that occurred in his first collapse were later repeated on the day of his death.
On 20 July 1973, Lee was in Hong Kong, to have dinner with former James Bond star George Lazenby, with whom he intended to make a film. According to Lee's wife Linda, Lee met producer Raymond Chow at 2 pm at home to discuss the making of the film Game of Death.
They worked until 4 pm and then drove together to the home of Lee's colleague Betty Ting Pei, a Taiwanese actress.
The three went over the script at Ting's home, and then Chow left to attend a dinner meeting.
Later Lee complained of a headache, and Ting gave him an analgesic (painkiller), Equagesic, which contained both aspirin and the muscle relaxant meprobamate.
Around 7:30 pm, he went to lie down for a nap. When Lee did not turn up for dinner, Chow came to the apartment but could not wake Lee up.
A doctor was summoned, who spent ten minutes attempting to revive him before sending him by ambulance to Queen Elizabeth Hospital. Lee was dead by the time he reached the hospital.
There was no visible external injury; however, according to autopsy reports, his brain had swollen considerably, from 1,400 to 1,575 grams (a 13% increase). Lee was 32 years old.
The only substance found during the autopsy was Equagesic.
On 15 October 2005, Chow stated in an interview that Lee died from a hypersensitivity to the muscle relaxant (meprobamate) in Equagesic, which he described as a common ingredient in painkillers.
When the doctors announced Lee's death officially, it was ruled a "death by misadventure".
Controversy occurred when Don Langford, Lee's personal physician in Hong Kong, who had treated Lee during his first collapse believed that "Equagesic was not at all involved in Bruce's first collapse".
However, Donald Teare, a forensic scientist recommended by Scotland Yard who had overseen over 1000 autopsies, was the top expert assigned to the Lee case.
His conclusion was that the death was caused by an acute cerebral edema due to a reaction to compounds present in the prescription painkilling drug Equagesic, where Teare concluded "death by misadventure".
The preliminary opinion of the neurosurgeon who saved Lee's life during his first seizure, Peter Wu, was that the cause of death should have been attributed to either a reaction to cannabis or Equagesic.
However, Wu later backed off from this position, stating that:
"Professor Teare was a forensic scientist recommended by Scotland Yard; he was brought in as an expert on cannabis and we can't contradict his testimony.
The dosage of cannabis is neither precise nor predictable, but I've never known of anyone dying simply from taking it."
Lee's wife Linda returned to her hometown of Seattle, and had him buried at lot 276 of Lakeview Cemetery.
Pallbearers at his funeral on 31 July 1973 included Taky Kimura, Steve McQueen, James Coburn, Chuck Norris, George Lazenby, Dan Inosanto, Peter Chin, and Lee's brother Robert.
Lee's iconic status and untimely demise fed many theories about his death, including murder involving the triads and a supposed curse on him and his family.
Black Belt magazine in 1985 carried the speculation that the death of Bruce Lee in 1973 may have been caused by "a delayed reaction to a Dim Mak strike he received several weeks prior to his collapse".
As well other authors have said the death of Bruce Lee may have been due to a "Vibrating Palm technique".
