Singer Amy Winehouse was more than five times over the drink-drive limit when she died, an inquest heard Wednesday, as a coroner delivered a verdict of death by misadventure.

Winehouse, 27, was found dead at her London home on July 23 following years of alcohol and drug addiction.

The inquest, in London, was told she had suddenly drunk heavily after abstaining from alcohol for three weeks and was poisoned by alcohol.

The singer had 416 milligrammes of alcohol per 100 millilitres of blood. The legal drink-drive limit is 80mg.

Coroner Suzanne Greenway said: "She had consumed sufficient alcohol at 416mg per decilitre (of blood) and the unintended consequence of such potentially fatal levels was her sudden and unexpected death."

Her father Mitch Winehouse has said that his daughter made repeated attempts to quit alcohol but without any medical supervision.

Following her death, Winehouse's 2006 album "Back to Black" has become the Britain's highest-selling album of the 21st century.

She rocketed to fame after winning five Grammy awards off the back of "Back to Black" and famously sang about her refusal to seek treatment for her addiction in her single "Rehab".

Winehouse was found in bed in her flat in the trendy north London neighbourhood of Camden on July 23.

Police recovered three empty bottles of vodka, two large and one small, from her home.

The inquest heard confirmation that a post-mortem examination of her body found her vital organs in good health and with no traces of illegal drugs.

But the high level of alcohol in her system probably stopped her breathing and plunged her into a coma.

Winehouse is believed to have come close to death four years earlier, in August 2007, following an overdose.

She was admitted to a London hospital after taking cocaine, ecstasy, ketamine and marijuana.

There were hopes that she could be returning to full health after she spent eight months on the Caribbean island of St Lucia, but her comeback soon fizzled out amid reports of shambolic performances at low-key concerts.