Carfentanil, a Schedule II controlled substance, carries a high risk of abuse, addiction and dependence.

Carfentanil is one of the most dangerous drugs to take hold in the U.S. In recent years, the sedative and tranquilizing drug — similar to fentanylaccounted for increasing overdose-related deaths because of its high potency and severe effects.

Carfentanil Facts at a Glance

  • There is no approved human medical use for carfentanil, which is an elephant and large animal tranquilizer.
  • Carfentanil is a Schedule II controlled substance.
  • Carfentanil is chemically related to fentanyl but is 100 times stronger.
  • Carfentanil is highly addictive. 

What Is Carfentanil?

Carfentanil was first synthesized in 1974 by a team of chemists. It has since been classified as a Schedule II substance under the Controlled Substances Act. Carfentanil is a synthetic opioid that is sort of a chemical cousin to fentanyl, which is an opioid that is used as pain medication and an anesthetic.

One of the major risks associated with the drug is that it can come in many forms. Carfentanil and fentanyl have been found mixed with heroin. This mixture increases the potency of each drug and makes heroin misuse much deadlier.

What Does Carfentanil Look Like?

Carfentanil is a white powder-like substance similar to cocaine or heroin. A similar appearance makes mixing the substances easier and creates a more potent drug.

Knowing how to identify the drug involves knowing carfentanil street names, which often refer to the substance mixed with other drugs. The most common street name is “gray death.” This mixture includes heroin, carfentanil, fentanyl and other opioids. The mixture is taken by injection, smoking or oral ingestion, but it gets its name from its similarity to concrete mix in appearance.

Why Is Carfentanil Mixed With Heroin?

Because carfentanil is cheap, has no odor or color and is highly soluble in water, it’s very common for drug dealers to mix it with other substances, such as heroin. Heroin is an opioid derived from morphine and creates a euphoric high for those who use it, making it highly addictive. However, when mixed with carfentanil, it can be deadly due to carfentanil’s extreme potency.

Carfentanil is sometimes treated like fentanyl, and people may not see the dangers of mixing the substances. However, combining the two can ultimately result in death. Because carfentanil is so hard to detect, heroin users may be unaware they are ingesting it due to the lack of defining characteristics that other substances usually have. It’s so difficult to recognize the presence of carfentanil in other substances that even medical examiners can have a hard time determining the drug’s presence.

How Strong Is Carfentanil?

Carfentanil, a synthetic opioid, is 10,000 times more powerful than morphine and 100 times more powerful than fentanyl, which is 50 times more potent than heroin. Even when veterinarians sedate a mammal with carfentanil, they must use gloves and face masks to prevent themselves from accidentally consuming the substance and potentially suffering from exposure because accidental contact can be dangerous. Carfentanil is not meant to be consumed by humans at all. However, this doesn’t stop drug dealers from cutting carfentanil into heroin.

What’s the Difference Between Carfentanil and Fentanyl?

Carfentanil and fentanyl have some key differences related to their strength. While both drugs are opioids, carfentanil is 100 times more potent than fentanyl. Because of this, carfentanil is only prescribed for large mammals like elephants, while fentanyl can be used in humans. Although both drugs cause overdoses, carfentanil is even more deadly than fentanyl because it is so strong.

Carfentanil Regulation

The DEA issued a nationwide warning in 2016 to the public and law enforcement about human misuse of carfentanil. The warning described the drug as a potent animal opioid sedative and one of the strongest opioids available.

The drug has a potency that is 10,000 times that of morphine, making it extremely dangerous and deadly to those who take it in large doses. Considering its strength, many individuals have asked what carfentanil is even used for. While the drug is used for large animals, including elephants, carfentanil use in humans remains unapproved due to the drug’s potency and addictive potential.

Carfentanil Addiction

Carfentanil addiction can be a concern if you take street drugs laced with the substance. Although there is no recognized medical use for carfentanil in humans, some street drugs may contain carfentanil. For those tolerant enough to potent opioids to not overdose on the drug, addiction can become a risk over time.

Is Carfentanil Addictive?

The addiction potential of carfentanil is similar to that of other opioids as it is a Schedule II narcotic. Misuse can create a dependence on the drug as a person’s body adjusts to carfentanil’s presence in the system. When tolerance builds, people begin to crave the drug and need larger doses to achieve the same desired effects. Unfortunately, mixing carfentanil and fentanyl into other drugs like heroin can cause people to become dependent on these opiates without knowing. That type of addiction can be more dangerous — mixing a drug with this potency and not having knowledge of its presence could easily lead to an overdose.

Effects of Carfentanil Addiction

There is no safe way to use carfentanil. The most common side effect of carfentanil use is death. If someone takes carfentanil and survives, they may experience symptoms similar to other opioid overdoses, including:

  • Breathing problems
  • Confusion
  • Constricted pupils
  • Decreased responsiveness
  • Delirium
  • Extreme sleepiness
  • Nausea and vomiting
  • Weakness

If you or someone you know is experiencing any of these symptoms, call 911 immediately. Carfentanil overdose is a medical emergency.

Carfentanil Overdose

The overdose risk of carfentanil is extremely high, even with very small amounts. The drug is, therefore, considered lethal. It is very easy to accidentally overdose on carfentanil due to its extreme potency. Some carfentanil overdose symptoms include:

  • Slowed or stopped breathing
  • Drowsiness
  • Confusion
  • Sedation
  • Small pupils

Multiple doses of naloxone, a drug used to reverse the effects of an opioid overdose, could be required to revive someone who overdosed on carfentanil.

How Much Carfentanil Can Kill You?

It is unknown how much carfentanil it takes to kill a person. The drug is 100 times more potent than fentanyl, and the amount of fentanyl equivalent to two grains of sand is considered deadly. This means that the amount of carfentanil it could take to kill a person could be much smaller.

How Long Does Carfentanil Stay In Your System?

The half-life of carfentanil, or how long half a dose stays in your body, is about 5.7 hours. Its breakdown product, norcarfentanil, has a half-life of 11.8 hours. Removing a drug from your system usually takes five half-lives, meaning carfentanil can stay in your body for around 28.5 hours. 

Carfentanil Withdrawal and Detox

When people become physically dependent on carfentanil, they may experience withdrawal symptoms when they stop using it. The most common withdrawal symptoms from opioids like carfentanil include:

  • Nausea and vomiting
  • Anxiety
  • Trouble sleeping
  • Hot and cold flashes
  • Sweating
  • Muscle cramps
  • Watery eyes and nose
  • Diarrhea

In some cases, withdrawal symptoms can be severe and even life-threatening. If you are experiencing withdrawal symptoms, it is important to seek medical help. With the right professional support, like what you would find at The Recovery Village, you can successfully overcome withdrawal and return to the life you want.

Carfentanil Withdrawal Timeline

The timeline for carfentanil withdrawal is not well-established since carfentanil has not been extensively studied in humans. However, withdrawal symptoms will likely begin within 8–48 hours of the last dose. The severity of withdrawal symptoms will vary depending on the individual’s use history and other factors.

Carfentanil Detox

If you are struggling with carfentanil addiction, it is important to seek medical help. Medically-assisted detox is the safest and most effective way to detox from carfentanil addiction. You should never try to quit “cold turkey” or detox at home from such a powerful drug.

The detox process involves three main steps:

  • Evaluation: A medical team will evaluate your addiction and create a personalized treatment plan. This plan will consider your use history, addiction severity and individual needs.
  • Detoxification: During detoxification, your body is cleansed of the toxins and substances contributing to your addiction. This process can be uncomfortable, but it is important to remember it is temporary. Medical professionals will monitor and support you throughout detox to make it as safe and comfortable as possible.
  • Transition: After detox, you will transition to the next treatment step. This may be an inpatient or outpatient rehab program. Treatment aims to help you recover from your addiction and live a healthy, sober life.

Treatment for Carfentanil Addiction

Many treatment options for carfentanil addiction are available, ranging from medical detox to inpatient and outpatient rehab. Medications may be prescribed with other forms of addiction treatment to ease your recovery from carfentanil, a strategy known as medication-assisted treatment (MAT). The Recovery Village offers a full continuum of care to help wean you off carfentanil and recover from your addiction.

Inpatient Rehab

Inpatient carfentanil rehab takes place in a residential facility. In inpatient rehab, you live on-site in a sober living environment and attend daily rehab sessions to help heal your body and mind and teach you the skills for a carfentanil-free life. 

Therapy options like cognitive behavioral therapy (CBT) or group therapy may be offered alongside life skills training. Support groups are also available, as are recreational activities. Options for inpatient rehab include residential rehab and partial hospitalization programs.

Outpatient Rehab

Outpatient carfentanil rehab is less intensive than inpatient rehab, often involving shorter sessions. In outpatient rehab, you live at home but attend sessions at the facility, although teletherapy options may also be available. Outpatient rehab allows the flexibility to go to work or school while focusing on your recovery. As with inpatient rehab, therapy, support groups and recreational activities are available. Outpatient rehab includes intensive outpatient and standard outpatient rehab.

Get Help With Carfentanil Addiction Today

If you or a loved one struggles with carfentanil, you may feel overwhelmed, and like there is no way out of the addiction. But help is available. At The Recovery Village, we are with you every step as you progress towards a carfentanil-free life: from medical detox to wean you off carfentanil to rehab to keep you off the drug. Don’t wait: contact us today to see how we can help.

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Editor – Theresa Valenzky
Theresa Valenzky graduated from the University of Akron with a Bachelor of Arts in News/Mass Media Communication and a certificate in psychology. She is passionate about providing genuine information to encourage and guide healing in all aspects of life. Read more
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Medically Reviewed By – Dr. Jessica Pyhtila, PharmD
Dr. Jessica Pyhtila is a Clinical Pharmacy Specialist based in Baltimore, Maryland with practice sites in inpatient palliative care and outpatient primary care at the Department of Veteran Affairs. Read more

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Medical Disclaimer

The Recovery Village aims to improve the quality of life for people struggling with substance use or mental health disorder with fact-based content about the nature of behavioral health conditions, treatment options and their related outcomes. We publish material that is researched, cited, edited and reviewed by licensed medical professionals. The information we provide is not intended to be a substitute for professional medical advice, diagnosis or treatment. It should not be used in place of the advice of your physician or other qualified healthcare providers.