The WA Police Force and ChemCentre confirm Hyoscine as the only drug detected at a home in Victoria Park where nine people overdosed.
Acting Deputy Commissioner Gary Budge said this incident was a sobering reminder that people taking unknown substances, be they illicit or prescription drugs, are seriously risking their health and wellbeing.
“Had it not been for the early 000 call and medical intervention on Tuesday night the consequences could have be much worse than they were," he said.
Hyoscine is a medicine used to control motion sickness, but has also seen used as a date rape drug, leaving victims slow and in a 'zombie-like' state.
Police are continuing to investigate the source of the drugs.
Some reports from Seven say a white powder arrived in the post from New York and was addressed to a man who no longer resides at the home on Colombo Street.
The same reports claim the powder wrapped in paper with the word 'Scoop' written on it was thought to be cocaine by the backpackers.
Scopolamine is another name for Hyoscine, which some people believe could explain the word scoop appearing in the envelope.
On Wednesday morning news broke of nine people being rushed to hospital all suffering from suspected drug overdoses.
Seven men and two women were rushed to three hospitals across Perth when a 000 call came just before midnight on Tuesday January 2.
Police later discovered all nine people, aged between 21 and 25 are visiting WA and the house they were staying at is used as temporary backpacker accommodation.
Police revealed the tourists as five French, two German and one Italian and Moroccan citizens.
Two people still remain in a critical condition in hospital.
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