What Is Carfentanil?

Carfentanil is a powerful derivative of fentanyl, a synthetic narcotic analgesic produced from morphine. While fentanyl is about 100 times more powerful than morphine, carfentanil is 100 times more potent than fentanyl, meaning it is 10,000 times more potent than morphine.

This drug is not approved for use in humans in any capacity, and it is typically found in veterinary medicine to sedate large animals, primarily elephants.

Carfentanil and Opioid Addiction

Carfentanil has been found in heroin and even fentanyl sold on the streets, starting in July 2016 in Ohio, when 35 overdoses and 6 deaths occurred in a span of 3 days. Law enforcement and emergency medical personnel warn that carfentanil sold illicitly looks like other drugs found on the street, including cocaine and heroin, because it is an odorless, white powder.

Individuals struggling with opioid addiction who purchase painkillers illicitly or use heroin are at risk of encountering opioids that are adulterated with carfentanil.

Carfentanil’s Extreme Potency

According to Elephant Care International, the dose of carfentanil safely administered to sedate a wild adult male African elephant, which can weight over 1 ton, is only 13 mg. A dose of fentanyl, 100 times less powerful than carfentanil, that can safely be administered to a human adult is up to 100 micrograms per hour – the equivalent of 0.1 mg. The dose for the elephant is equivalent to 13,000 micrograms of carfentanil, which is about 1.3 million micrograms of fentanyl. Hence, 1,000 mg of fentanyl, the equivalent in potency of 1 mg of carfentanil, will easily kill a human.

According to an article from the Washington Post, carfentanil’s deadliness can be expressed in a few ways. First, the Buffalo Field Campaign based out of Yellowstone National Park warns that humans should not eat the meat of bison who have been sedated with carfentanil, because it can enter the human’s body and cause an overdose. Second, Russian authorities used a weaponized chemical gas based on carfentanil to end a Chechen hostage crisis in 2002 and ended up killing 170 people with one dose.

Because of carfentanil’s potency, the effects on the human body and brain are very rapid. Even in elephants, the sedative effects are especially rapid. According to Elephant Care International, veterinarians must watch elephants for signs of pulmonary edema and capillary bleeding, characterized by a pink foam issuing from the elephant’s trunk, which indicates a potentially fatal rise in blood pressure. When even a fraction of the dose given to elephants is administered to humans, onset is rapid, difficult to stop, and hard to treat.

Carfentanil Effects & Overdose Signs

The effects of carfentanil are similar to those of heroin but, due to the potency, can result in an almost immediate overdose. Overdose symptoms may begin within minutes of exposure to the powerful narcotic.

Signs of a carfentanil overdose include:

  • Sudden extreme drowsiness
  • Tiny pupils
  • Slowed or stopped breathing
  • Disorientation
  • Clammy skin
  • Loss of consciousness

Response to an Overdose

A timely response to a suspected overdose can mean the difference between life and death. If you suspect an overdose involving carfentanil or any other opioids, call 911 immediately and administer naloxone if you have it. 


The effects of an overdose may be reversible via the use of naloxone. Naloxone is a medication that was specifically designed to quickly reverse the effects of opioids in the event of an overdose. Medical professionals will often administer this medication via injection, but auto-injectors were recently approved for public use. If one has access to an auto-injector, it should be used on the outer thigh of the individual suffering from an overdose. Due to the potency of carfentanil, one dose of naloxone may not be adequate to reverse an overdose, and additional doses may be required.

Naloxone can be obtained at pharmacies without a prescription in many states.

Help for Opioid Addiction

People who struggle with addiction to opioid drugs, especially heroin, are at increased risk of consuming carfentanil at some point. There are many reasons it is important for a person struggling with opioid addiction to seek help, including the risk of overdose, and now it is more important than ever.

There are many rehabilitation programs that can help a person safely detox from opioid drugs. These programs should be followed by individual and group therapy, so the person not only ends their physical dependence on the drug, but also gets help to overcome psychological effects of addiction. Clients will learn coping mechanisms for triggers or stress that may have previously led them to abuse heroin or other opioids.

It is very possible to overcome an opioid addiction, with the right rehabilitation program and the support of family and friends. Call us today at to learn more about addiction treatment near Miami, Florida at Recovery First.

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