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.
Fourth teenager arrested in Plymouth murder investigation
It's after a body was found in a marina
Man dies in rural Devon crash
Investigations are ongoing
Devon teenager charged with murder
19-year-old Layton Randle to appear at court
Dramatic bedroom window rescue of flood-hit resident
Man and dog evacuated from East Devon home
Storm damage to West Hoe Pier could cost extra £200,000
West Hoe Pier was hit "at most vulnerable" stage
Storm Chandra causes disruption across Devon
School closures and travel chaos across county
