An experimental chemical called W-18, identified as extremely dangerous, has surfaced in Saskatchewan where it has been linked to other worrisome street drugs associated with a number of fatal overdoses.

A warning from the College of Physicians and Surgeons of Saskatchewan said health care providers should use "extreme vigilance and caution when treating cases of overdose in the province where Fentanyl and similar drugs are suspected."

The college cited information from a federal drug testing agency of Health Canada which confirmed that W-18 was detected in a counterfeit tablet of Oxycodone in the Kerrobert area, which is about 180 kilometres west of Saskatoon.

Saskatchewan RCMP also confirm W-18 was detected in 1 of 3 counterfeit Oxycodone pills seized in that bust, and said in a release that "street drugs are often represented as one thing while being something completely different."

Chemical created at the University of Alberta

W-18 is described as "a dangerous and potentially deadly synthetic research chemical" which can even be hazardous when simply being handled.

W-18 can be found for sale online in China but it is not something that was created in a lab there.

It was invented much closer to home - at the University of Alberta in the 1980s. The experimental painkiller was patented by three men - one who still lives in Edmonton.

"The researchers were unsuccessful, sort of put it on the shelf and there it sat for numerous decades. When it was rediscovered, we believe out of China, and then reproduced and incorporated into the illicit drug market," said Julia Bareham, the manager for the Prescription Review Program with the College of Physicians and Surgeons of Saskatchewan.

"We see it being mixed in with drugs like Oxycodone, maybe fentanyl as well. We don't really know if it's an opioid, like morphine or fentanyl, but we know it's a substance we need to be very cautious with because we don't know how it works and we really don't understand its pharmacology," Bareham said.

The drug was never marketed to be used on humans or animals as a painkiller. According to Bareham, W-18's creators required 1-10,000th of a dose to get the same effect as morphine.

W-18 found in Saskatchewan overdose in 2015

25 year-old man who died of a drug overdose in Saskatchewan in 2015 had W-18 in his system. The coroner was unable to determine whether W-18 caused the overdose but it was found along with fentanyl and morphine.

CBC contacted the Saskatoon and Regina Police but both said they have yet to come into contact with W-18.

Warning to health care workers

"Physicians, particularly emergency room physicians, hospital staff and other emergency respondents should be aware of the potential for exposure to the substance when responding to an emergency situation," the college said in a media release.

Dr. Karen Shaw, registrar of the college, said informing physicians of the situation may help ensure that safeguards are in place to avoid a dangerous situation.

"We also wish to ensure that appropriate care continues to be provided to patients who find themselves in distress due to an overdose," Shaw said in the release.

The college noted that there is limited information about whether or not the use of naloxone in treating a W-18 overdose is effective. However, the college added that since W-18 is often combined with opioid drugs the use of naloxone as a counter-treatment is still recommended.