Grant Hackett forced to relive Stilnox dramas

Swimmer Grant Hackett has been forced to relive his troubled past after his father revealed a death threat led to his addiction to prescription medication.

Speaking exclusively to 7News, Hackett says he understands why his dad Neville broke his silence, but he just wants to move on.

"It's something I don't want to openly discuss but at the end of the day people don't understand the ups and downs of the last few years and the pressures associated with that", says Hackett.

Grant's father Neville says his son turned to the drug after a threatening phone call two years ago.

It's not the first time he's gone public with his problems.

"I think even my dad reading some of the articles about his son during the week and how people get things so wrong and the lies...it just gets a bit frustrating for them."

Neville says Grant was threatened by well-known criminals in Melbourne and that prompted him to start using Stilnox.

“His life was threatened by a well-known associate of criminals — that’s a fact” said Hackett snr.

“This happened about two years ago when he was forced to immediately leave Melbourne to live in Sydney. The truth about this has never come out.

“That’s what really caused the Stilnox abuse and the addiction.

“I know he used Stilnox while he was swimming but he wasn’t hooked on it. It was when his life was threatened and he couldn’t sleep at night from all the worry.”

The news comes after Hackett made a stunning comeback in the pool this week, qualifying for the Australian team for this year’s world titles in Russia.

He's the oldest swimmer ever to make the Aussie team.

"Now it's just about doing it for all the right reasons, and whilst I have that feeling and desire I'll keep doing it, it might take me to the Olympic games and it might not."