A synthetic opioid 25 times more powerful than fentanyl has made its way to the Quebec City region, where public health officials reported Saturday they have detected the dangerous compound in pale green tablets that mimic the appearance of other prescription opioids.

The Quebec City regional public health authority warned the compound, protonitazepyne, presents a high risk of overdose, which may require several doses of the life-saving medication naloxone.

Health Canada first detected the substance in 2023 and would go on to positively identify it in a total of 25 drug samples by the end of the year. Public health officials working in the Quebec City-area now say it has been increasingly found in the Montreal area since the beginning of 2024.

No overdoses in the Quebec City region have been linked to the protonitazepyne tablets, but officials say it presents a very real threat.

However, its clear that given the potency and the fact that its in a tablet of something else, the risk of overdose is very high for people who would consume this tablet, Dr. Anne-Frédérique Lambert-Slythe with the Quebec City public health authority said in an interview.

Officials further warn that protonitazepyne does not show up on test strips designed to detect fentanyl.

The Quebec City public health authority is reiterating advice for people who use drugs to avoid consuming substances alone and to keep naloxone nearby. The medication is available for free at pharmacies.