Emergency room doctors and nurses in Vancouver suspect a drug originally used to tranquillize elephants might be the reason they've had to drastically increase their supply of a life-saving opioid antidote.

Carfentanil is the most toxic form of synthetic opioid. Authorities believe it's being manufactured in clandestine labs in Asia and smuggled to Canada in small packages.

At St. Paul's Hospital in downtown Vancouver, the doctors and nurses who treat a constant stream of overdose patients believe they're seeing the drug's dangerous effects up close.

Dr. Kevin Nemethy says a single dose of opioid antidote naloxone (brand name Narcan) used to be enough to wake up an overdose patient.

"Now we are not finding the desired effect until we give 10 times the dose or even 20 times the dose of naloxone," he told CBC News during a particularly busy shift on Nov. 24 — the day after the last provincial social assistance cheques were issued.

Dr. Kevin Nemethy says doctors now have to give a much higher dose of naloxone to revive overdose patients. (Frederic Gagnon/CBC)

Tanya Campbell, the emergency department's nurse leader, says the number of overdoses is overwhelming and the patients appear to be taking stronger drugs.

"We actually start them on a continuous drip of Narcan, if they are not waking up," she said. "Sometimes we have to take over their airway till they get the drugs out of their system and they wake up."

B.C. lab can't test for carfentanil

She says she believes some patients get tricked into buying opioids like carfentanil when they think they're buying heroin.

Vancouver police have confirmed they've seized drugs containing carfentanil. But the province's coroner has yet to confirm how many of the 755 overdose deaths in B.C. so far this year are linked to the drug because its toxicology centre can't test for it.

The Provincial Health Services Authority says the lab received the necessary licence last week, but equipment needs to be calibrated and testing for carfentanil won't start for two to three months.

Alberta's lab is already equipped and has linked the drug to 15 deaths.

'It's overwhelming,' says nurse Tanya Campbell, seen here helping a patient who overdosed in the hospital bathroom. (Fred Gagnon/CBC)

Nurse Campbell fears naloxone will soon be no match for carfentanil.

"I think that's a fear that all of us have as health-care workers," she said. "That one day, we are not going to be able to even try to save these people.

"We're going to have a horrific amount of people dying on the street because we don't know what they are taking."

Concern that naloxone won't always work is 'a fear that all of us have as health-care workers,' Campbell says. (Frederic Gagnon/CBC )

Officials at St. Paul's say there was a night in late October when the emergency room was so overwhelmed with overdose patients, they nearly ran out of naloxone and had to get a delivery from a nearby hospital.

"That's unheard of and we're the overdose centre of Vancouver, maybe Canada," said Dr. Dan Kalla, head of the emergency department.

"We are going through so much because we require so much naloxone … the demand is outstripping the supply."

CBC News Investigates

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