Veterinary expert warns of the dangers of carfentanil

A veterinary expert says he's "horrified" a drug used to sedate large animals like elephants, rhinos and bison has led to the deaths of two men in Alberta.

Earlier this month, traces of the opioidcarfentanilwere found during autopsies of two men in their 30s from Edmonton and Calgary.

Carfentanil is 100 times more potent than fentanyl, a drug that hasalready killed153 people in the first half of this year.

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As head of the Department of Veterinary Clinical and Diagnostic Science in the Faculty of Veterinary Medicine at the University of Calgary,NigelCaulkettisfamiliar withcarfentanil. He's used it to immobilize large wild animals.

Caulkettsaidveterinarianswould wear full safety equipmentwhen handling the drug, and in many zoosa paramedic had to be present when it was being used.

Less potent alternatives tocarfentanilare becoming more commonly used by veterinarians, he said.

"The reason we usecarfentanilor used to, we can no longer get it is because I can use one millilitre, or one small dart ofcarfentaniltoanaesthetizea full grown male bison," Caulkett said.

"One drop of the carfentanil we used to work with was equal to sixtimes the lethal dose of morphine."

Those of us that work with it know it's an extremely potent and powerful drug, so the thought of it being on the street is quite scary.- NigelCaulkett, veterinarian

Having handled the drug, Caulkett was shocked humans were using it, but says it's not the first time in hisfield that they've lostdrugs used for wildlife capture due to human abuse.

"I was fairly horrified, my colleagues and I found out a few months ago that carfentanil had hit the streets in the U.S. and we were wondering when it might reach Canada," he said.

"Those of us that work with it know it's an extremely potent and powerful drug, so the thought of it being on the street is quite scary."

Alberta Health says dealers are adding it to traditional drugs, sometimes without telling their users.

Alberta's acting chief medical examiner, Dr. Elizabeth Brooks-Lim, said one of the men who died also hadfentanyl in his system.

The drug resembles table salt, andCaulkett said hebelieves that and its potency is why it hasended up on the street.

Caulkettsaid hehopes Alberta Health sounding the alarm will be enough to warn people about the drug.

"Giventhe extreme potency, the chance of mixing it up improperly, the difficulty reversing it, the amount of antagonist that's required in the field and also the duration, it's a very deadly drug."