Oxford County residents are being warned about a "very toxic" form of fentanyl that has arrived in the area.
According to Southwestern Public Health there have been two overdoses related to red fentanyl in the past week, including one that was fatal.
Public health officials added that it is likely the potent drug is also circulating in neighbouring counties.
People who use illicit substances are advised not to use alone, avoid mixing drugs, only to take small amounts to start, and to carry a naloxone kit.
Naloxone kits, which can temporarily reverse the effects of an overdose, are available through the health unit for anyone who wants one.