Heartbreaking Final moments of man taking own life (Video)

A euthanasia advocate's final moments after downing a poisonous concoction were recorded in a bid to clear his family of any wrongdoing.

Max Bromson, who had terminal bone cancer, was filmed by his sister as he drank a fatal dose of a killer drug in July 2014 - and died three minutes later.

Shot in a motel room in south Australia, he can be seen hugging a pillow dressed in a hat and gloves and still wearing his glasses.

The clip shows Max with his head down and a member of his family stroking his hand, before his left arm goes limp and the 66-year-old man dies.

His sister, Kerry Bromson, told ABC news that the family chose to record the moment to prove they had nothing to do with his death.

She said: "We were doing it out of love for our brother, or father, it wasn't a conscious thing about what would happen out of this."

Police carried out an investigation into the circumstances for two years before the family were cleared of wrongdoing, according to 9news.com.au .

Max was first diagnosed with terminal bone cancer in 2009 with doctors telling him he only had six months to live.

But he lived with "excruciating" pain for another five years.

Eventually, he tried to find ways to end his life and discovered Exit International, a euthanasia advocacy group.

He then acquired the drug he required without telling his family how he managed to get hold of it.

He became an advocate for voluntary euthanasia but when his condition became worse he decided to take the drug before he was too frail to administer it himself.

Had he left it any later it could put his family at risk of prosecution.

And Kerry explained: "He just said to us, 'I can't wait, I can't. Not any longer, I can't take it.'"

A bill to legalise voluntary euthanasia is expected to be debated in South Australia's state parliament in the next few weeks.