E-cigarettes, designed to help people quit smoking, could act as a "gateway" to trying more harmful illicit drugs, researchers claim.
Like conventional cigarettes, the devices, which contain "pure nicotine", are said to raise the addiction to banned substances such as cannabis and cocaine.
In tests on mice, US neuroscientist Professor Eric Kandel found they developed a need for cocaine and warned this could have the same effect in humans.
E-cigarettes, designed to help people quit smoking, could act as a "gateway" to trying more harmful illegal drugs such as cannabis and cocaine, researchers claim.
Like conventional cigarettes, the devices, which contain "pure nicotine," are said to raise addiction levels, particularly to cocaine as revealed in tests on mice.
US neuroscientist Professor Eric Kandel, who carried out the research with his wife Dr Denise Kandel, warned this could have the same effect in humans.
He said: "E-cigarettes have the same physiological effects on the brain and may pose the same risk of addiction to other drugs as regular cigarettes, especially in adolescence during a critical period of brain development.
"We don't yet know whether e-cigarettes will prove to be a gateway to the use of conventional cigarettes and illicit drugs, but that's certainly a possibility."
The findings are published in the New England Journal of Medicine.
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