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Cannabinoids, Synthetic


Gerald F. O’Malley

, DO, Grand Strand Regional Medical Center;

Rika O’Malley

, MD, Albert Einstein Medical Center

Last full review/revision Jun 2020| Content last modified Jun 2020
Click here for the Professional Version

Cannabis is a term for marijuana. Tetrahydrocannabinol (THC) is the main active ingredient in marijuana. Synthetic cannabinoids are man-made drugs that are similar to THC. They are usually sprayed on dried plant material and smoked or inhaled as vaporized liquid from e-cigarettes. There are many chemical families of synthetic cannabinoids, and new compounds are being reported regularly.

(See also Drug Use and Abuse.)


Different cannabinoids have different effects, and many of the short- and long-term effects remain unknown. However, there are three main categories of effects:

  • Psychiatric: Confusion, agitation, hallucinations, and psychosis (loss of contact with reality) that may be irreversible

  • Cardiovascular: High blood pressure, rapid heartbeat (tachycardia), and heart attack

  • Neurologic: Blurred vision, heavy sweating, and seizures

Additional effects include vomiting, high body temperature (hyperthermia), muscle breakdown, and kidney failure.


  • A doctor's evaluation

Doctors usually make their diagnosis based on what drugs people or their friends say were taken. Routine urine drug tests do not detect synthetic cannabinoids, although there are specific tests to detect synthetic cannabinoids in blood, urine, or hair.

People who show signs of severe acute intoxication often need tests to look for complications. Doctors typically do blood tests to check blood count, electrolytes, and kidney function and do an electrocardiography (ECG) to check heart rhythm. Their urine also may be tested for myoglobin, which indicates muscle breakdown.


  • IV sedatives

  • IV fluids

Typical treatments, which include IV sedatives (benzodiazepines) and fluids and supportive care, are usually adequate. People with dangerously high body temperature (hyperthermia), persistently high heart rate or agitation, and high serum creatinine (indicative of possible kidney problems) should be hospitalized and monitored for muscle breakdown and heart and kidney damage.

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