What is carfentanil?


Carfentanil is an extremely potent synthetic opioid initially developed as a tranquilizer for large animals, such as elephants. It is not approved for human use but has been found in street drugs, making it important to be aware of its presence and the extreme risk it poses.

Medical formulations

Carfentanil is available as injectable solutions for veterinary use only.

Street names

Carf, Elephant tranquilizer, Gray death

Historical context

Carfentanil was first synthesized in the 1970s by Janssen Pharmaceutica. It has no approved medical use for humans, but it has gained notoriety in recent years for its appearance in street drugs and its association with numerous overdose deaths.

How long does carfentanil stay in your system?

Carfentanil has a half-life of about 7.7 hours. It takes approximately 38.5 to 46.2 hours for the drug to be completely eliminated from the body.


Carfentanil is a white, crystalline powder that is often mixed with other substances or disguised as other drugs, making it difficult to identify.

Warning: Consuming illicit drugs, including pressed pills, may result in unintended fentanyl exposure, leading to potentially fatal consequences. Exercise caution and consider using fentanyl testing strips to identify the presence of this dangerous substance in street drugs.

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