There's no good antidote for super heroin laced with elephant tranquilizer

In the wake of hundreds of drug overdoses in the U.S. linked to the elephant tranquilizer carfentanil, experts are warning that a common overdose antidote isn't strong enough to counteract a substance that's about 100 times more potent than fentanyl and 10,000 times more potent than morphine.

Carfentanil is the powerful synthetic opioid used commercially for subduing large animals but recently connected with hundreds of overdoses across the US. First responders have been using naloxone, also known by the brand name Narcan, as a life-saving measure to reverse the effect of overdoses. Narcan can reverse the effects of a heroin overdose almost instantly, but carfentanil is so powerful that first-responders say many overdose victims are requiring multiple doses to counteract its effects.

After police in Winnipeg, Manitoba, seized 1,477 blotter tabs earlier this month containing carfentanil, the head of the city's firefighters union told reporters his team has treated at least two young men who recently overdosed on the drug. Alex Forrest said that at least four doses of naloxone were required to revive them both, double the amount contained in the kits distributed by the Winnipeg health authority. It typically comes with two doses and is usually injected into a muscle, but it's also available in other forms, such as nasal spray.

"You can't have too much naloxone in your community," Michael Parkinson, coordinator for the crime prevention council of the Waterloo region in Ontario, told VICE News in response to the events in Winnipeg. "Two doses clearly isn't enough to save people's lives or reduce the injury from overdoses that do not result in death," he added.

Parkinson said hospitals should revisit their policies and provide overdose victims with naloxone kits to take home, something that's not happening yet. Health Canada did not immediately respond to a request for comment.

Carfentanil is part of a new generation of synthetic opioids which can be fatal in doses that are the equivalent to the size of a single grain of salt. Police officers have begun arming themselves with the antidote in case they accidentally inhale or touch drugs that contain fentanyl or carfentanil.

Both the US and Canada have promised to improve naloxone access and make it available without a prescription. Until recently, it was only available through select first responders and health professionals. Numerous state and provincial health jurisdictions have vowed to make it more readily available in pharmacies without prescriptions.

In Hamilton County, Ohio, health officials have confirmed 12 fatal overdoses linked to carfentanil in recent months. Local authorities there are sounding the alarm over difficulties with relying on naloxone to prevent and reverse these types of opioid overdoses.

Tim Ingram, the county's health commissioner, recently told NPR that it takes hours for the body to metabolize carfentanil, longer than other opioids.

That means that after the naloxone wears off, users can still have enough carfentanil in their system to cause another overdose.

Ingram explained that many carfentanil overdose victims there have required more than two doses, and he's trying to get a more concentrated version of naloxone distributed in the near future.

Ohio attorney general Mike DeWine echoed Ingram's concerns last week, and warned that even when overdose victims are given naloxone and brought to the hospital, they still risk dying of an overdose after they're discharged.

"So what we are now seeing happen is that people are brought back to life, taken to a hospital, are advised to stick around, they feel ok so they walk out the door and two hours later, they are dead because it didn't stay in their system long enough," he said.

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