The 53-year-old Killara resident died on board an Albury-bound V/Line train on October 6 last year.

He boarded the train at Melbourne, collapsed and could not be resuscitated.

A blood test showed he had a synthetic cannabinoid in his system known as Cumyl-PeGACLONE.

A pathologist performed an autopsy, which found the man had heart problems.

The death of the father-of-two, known only as Mr P, was investigated by coroner Audrey Jamieson, who noted the drugs could induce cardiac arrhythmia.

She found synthetic cannabis could be more dangerous than regular marijuana, with 12 Victorian deaths from 2017 to 2019 under review.

"There is so little definitive information about the effects of novel synthetic substances and there is no practicable way for a user to know precisely which illicit synthetic drugs are being consumed," Ms Jamieson said.

"It thus seems unlikely that Mr P and other users of synthetic illicit drugs would or could anticipate any potential increased risk to health and life.

"The combination of limited information and general ignorance about the potential risks of synthetic illicit drugs presents a unique challenge to health and governance policy makers."

It was unclear how the late man obtained the drug.

Ms Jamieson urged the Department of Health and Human Services to review how synthetic drug education was provided to health services and give training to clinicians if necessary.

"The full range of harms and risks associated with synthetic cannabinoid use is not well understood, in part because of a lack of studies," she said.