Australian teenager Melanie Boyd begged her friends to call for help after taking a lethal cocktail of booze and drugs, an inquest was told.

But by the time an ambulance was called, three hours after she was found "blue" and “struggling to breathe,” the popular Townsville private school student, 16, was dead.

In a tearful apology Thursday, Matthew Aubrey, 20, told an inquest into her June 2006 death that the first-time drug taker wanted to call for help when two fellow drug users at the "pharm party" fell into fits of convulsions.

"Mel had a phone, she said if it's happened to them I don't want this to happen to me," Aubrey told the Townsville Coroner's Court.

But the six partygoers talked each other out of calling for an ambulance — because they did not want to involve the police.

"It was not my party, not my house, not my call," said the youth, who was 18 at the time and the oldest at the party.

"Knowing what I know now, I wish I was smarter."

Parents Laurie and Julie Boyd angrily refused to accept his emotional plea for forgiveness as well as that of the teenage girl who supplied the drugs and hosted the beachfront house party.

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