What Is A Lethal Dose Of Carfentanil?

Carfentanil is widely considered the most potent fentanyl analog available in the United States, and one of the most dangerous substances encountered in the illicit drug supply today. Originally developed as a large animal tranquilizer, carfentanil is a synthetic opioid that is estimated to be roughly 10,000 times more potent than morphine and 100 times more potent than fentanyl. It is classified as a controlled substance with a high potential for abuse and chemical dependency, and has no approved medical use in humans.

The lethal potential of carfentanil is extreme. An overdose can occur with as little as two milligrams of the substance, an amount so small it is barely visible to the naked eye. Because carfentanil is often mixed into street drugs like heroin or counterfeit pills without the buyer’s knowledge, the risk of accidental overdose is significant. Even brief skin contact or accidental inhalation can be enough to cause a serious medical emergency, making carfentanil one of the most dangerous substances law enforcement and first responders encounter in the field.

Learn more about the lethal doses of commonly abused drugs

What To Know About A Lethal Dose Of Carfentanil

The lethal dose of carfentanil is 2 mg, the same legal dose of fentanyl. But a person can respond to a dose as low as 1 microgram, which is 0.001 mg. Carfentanil was originally created in 1974 by a team of chemists with the purpose of tranquilizing large animals in veterinary work. It was never meant for human consumption.

This opioid is extremely powerful, as it’s:

• 100 times more potent than fentanyl
• 4,000 times more potent than heroin
• 10,000 times more potent than morphine

A dose of carfentanil the size of a grain of salt could be lethal.

Why Is Carfentanil So Dangerous?

Drug dealers have been adding carfentanil to other illicit drugs because it’s potent, easier to obtain than heroin or cocaine, and it’s cheaper. Carfentanil is odorless and colorless, so it’s most likely that if a person unknowingly purchases carfentanil-laced heroin, cocaine, or another drug, it would be undetectable.

Carfentanil can also be absorbed into the body accidentally through airborne powder. Each of these factors increases the chances of an overdose, causing numbers of opioid-related deaths to spike.

Signs Of Carfentanil Overdose

If you are worried that you or a loved one have overdosed on carfentanil, there are a few warning signs to look out for.

Some of the warning signs of carfentanil overdose include:

• pinpoint pupils
• unresponsiveness
• an inability to speak or move
• vomiting
• dilated pupils
• bluish color to the lips, tongue, nails, or skin

If you are experiencing signs of overdose, call 911 and administer naloxone immediately via injection or nasal spray. This will reverse and block the effects of carfentanil.

What To Do If You Suspect A Carfentanil Overdose

If someone is showing signs of a carfentanil overdose, every second counts. Call 911 immediately and administer naloxone if it is available, either by injection or nasal spray. Because carfentanil is so much more potent than other opioids, multiple doses of naloxone may be needed to reverse its effects. Do not leave the person alone while waiting for emergency services to arrive, and try to keep them on their side to prevent choking if they are vomiting or unresponsive.

It is also important to take precautions when handling any substance that may contain carfentanil. Because the drug can be absorbed through the skin or inhaled as an airborne powder, direct contact should be avoided whenever possible. First responders and bystanders should avoid touching unknown substances with bare hands. Carrying naloxone is strongly recommended for anyone who uses illicit drugs or spends time around people who do, as it is a safe and effective tool that can mean the difference between life and death in a carfentanil overdose situation. Naloxone is available without a prescription at most pharmacies across the United States.

Getting Treatment For Carfentanil Addiction

For more information about addiction treatment options, browse our directory or reach out to the Substance Abuse and Mental Health Services Administration (SAMHSA).

Written by the Addiction Resource Editorial Staff