This 22-year-old took a drug to quit smoking. Eight days later, he took his own life.

This common medication comes with an important health warning in the US, but not in Australia.

Timothy Oldham was a strong student and a champion tennis player.

But all his mother has left of the 22-year-old is a voice recording he made before he took his own life – just eight days after taking the quit-smoking drug, Champix.

Now, a Queensland coroner will review all suicides of people who used the drug amid growing concerns of link between the two.

This link between the medication and mental health has already been discovered in the US, where the drug (known as Chantix) has carried a ‘black box warning’ about side effects since 2009, after pharmaceutical company Pfizer settled a class action taken against them by 3,000 plaintiffs.

But the Australian version carries no such warning.

Phoebe Morwood-Oldham says her son – who suffered anxiety but had never mentioned or attempted suicide before – could have been saved had she known about the side effects.

She has started a Change.org petition campaigning for warnings, which has already gathered more than 32,000 signatures.

Ms Morwood-Oldham says the death of her “beautiful boy” still “hurts so deep”.

She says there are reports of 25 suicides in seven years linked to the prescription drug, but still no warning.

“If I knew of the dangerous health side-effects possible with Champix, I never would have allowed him to keep taking it,” she says.

“But we were never told by the doctor, or on the packaging. We assumed it was safe.”

The devastated mother says her son began acting strangely and completely out of character just four days into the prescription.

“I went to bed and I got up and he’s sitting at his door on a cushion with my electric chainsaw plugged in, telling me there are people coming to get him,” she told the ABC’s 7.30.

Four days later, he hung himself.

Related: New anti-smoking campaign labelled as sexist… but we suspect it will work.

Dr Diana Zuckerman – head of America’s National Centre for Health Research and a former policy advisor to Hillary Clinton – said the drug had “many more adverse reactions that have been reported than pretty much any other drug”.

“It seems very clear that people who would never have thought about suicide before, when they are taking this drug, they start thinking about it,” Dr Zuckerman told 7.30.

“And sometimes they act on those thoughts and actually try to kill themselves or they do kill themselves.”

Saturday Night Live acknowledged the serious side effects of Chantix in this skit (post continues below):

But Australia’s Therapeutic Goods Administration doesn’t require a ‘black box’ warning, saying it contains “appropriate information to assist in its safe and effective use”.

Within three years of Champix’s 2007 introduction in Australia, 900,000 prescriptions had been filled and more than 200 suicide-related events had been reported.

Australian health professionals say studies show it is nicotine withdrawals that cause mental health issues, not Champix.

That’s a question the coroner looking into Timothy’s death – and plenty of others – will have to decide.

But, Ms Morwood-Oldham will continue her relentless campaign regardless.

”Nothing will bring back my boy,” she says.

“But please help me ensure no one else lives through this devastation when clear warnings might save them.”

You can sign her petition here.

If this post brings up issues for you, contact Lifeline on 13 11 14.

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