A highly dangerous synthetic cannabis is either sprayed on to herbal smoking material or added to cigarettes in powder form.
Public Health England says the chemicals known as 'spice' can cause sickness and convulsions - and while there haven't been any cases recorded in Devon, the substance may well be available here.
The Exeter drug and alcohol charity RISE wants to pass the warning on to local residents.
Exeter care agency rated 'inadequate' and in special measures
Bosses at Horizon Care insist change
Raw sewage spews into Plymouth suburb estate and woods
Concerns raised for public health and wildlife in Woolwell
Councillor stands under trees to stop chainsaw massacre
Emergency preservation order now in place
Three years jail for charity box thief
And he can't eat in McDonald's for eight years
Spat over whether 'inadequate' children's services are as bad as MP suggests
Exeter's Steve Race believes they are in 'last chance saloon;
