Six young people were taken to NSW emergency departments within eight days of each other in June after they each smoked nicotine vapes.
The patients experienced symptoms including seizures, loss of consciousness and vomiting, according to a report from the Sydney Morning Herald.
NSW Health raised the alarm amongst state doctors with a memo sent to South West Sydney Local Health District hospital doctors following the incidents, which occurred between June 21 and 29.
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Its believed the the majority of the incidents occurred in the south-west Sydney area.
NSW Health believes some of the vapes were purchased from sellers on social media platform Snapchat, according to the Sydney Morning Herald report.
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Subsequent analysis of the vapes showed they contained nicotine.
Nicotine vapes can only be purchased with a prescription under Australian law.
It is illegal to sell vapes to anyone under 18.
Two high school students were taken to hospital after suffering a severe reaction to a vaping product in Melbourne in May.
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