Synthetic Cannabinoids: Dangers, Legalities, and Origins

Human-created and hazardous

Synthetic cannabinoids are human-created chemicals similar to some of those found in marijuana. They have mind-altering properties and can be smoked or vaporized, depending on the form. Hundreds of brands are on the market and a lot of people use them because they mistakenly believe they’re safe and legal.

However, they’re not considered safe and many of them are illegal. This so-called fake marijuana, or fake weed, is sometimes called herbal incense or liquid incense. They are marked “not for human consumption” by manufacturers who want to avoid legal consequences for selling them.

Three brightly colored packets represent packaging of synthetic cannabinoids.
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What They Are

The word cannabinoid refers to any of the chemicals naturally found in the cannabis plant, from which we get marijuana. The best-known natural cannabinoids are delta-9 tetrahydrocannabinol (THC), which is what makes you high, and cannabidiol (CBD), which has numerous medicinal uses and doesn’t create a high. (The plant contains hundreds of other active compounds as well.)

Synthetic cannabinoids are chemically similar to those that occur naturally in cannabis, but at this time, no standards for manufacturing or selling them exist.

They’re often marketed as safe, natural, and legal alternatives to weed. However, they tend to have unpredictable effects on your body and can be significantly more dangerous than their natural cousins. Some of these effects can even be life-threatening.

The people most likely to use synthetic cannabinoids are men in their 20s who use multiple drugs.

Brands of synthetic cannabinoids include:

  • K2
  • Spice
  • Joker
  • Black Mamba
  • Kush
  • Kronic
  • Mr. Happy
  • Scooby Snax
  • Cloud 9
  • Mojo

Many others are on the market, as well.

How They Work

Your body has a system named for processing cannabinoids, and it’s called the endocannabinoid system. In that system, special brain receptors bind with the different chemicals. Synthetic cannabinoids bind with the same receptors as THC and therefore have a somewhat similar effect on the brain.

However, some of the synthetics form a stronger bond, which means they produce a much stronger effect. On top of that, the chemical composition may change from brand to brand and even batch to batch of the same brand, which means the effect can be different each time you buy them.

Adding significant danger, some synthetic cannabinoids are contaminated with toxic chemicals—including rat poison. Or, they can be laced other drugs, including synthetic opioids such as fentanyl or synthetic cathinone drugs like “bath salts” and “flakka.” Some people have died due to hazardous ingredients that they didn’t know were in the product.

Synthetic cannabinoids are often sprayed onto dried plant material so they can be smoked, brewed into tea, or added to food. They’re also sold in liquid forms that can be vaped in e-cigarette devices.

Health Effects

Some of the effects of synthetic cannabinoids on your brain are similar to those of marijuana, including:

  • Relaxation
  • Mood elevation
  • Altered awareness and perception
  • Psychosis (detachment from reality)
  • Anxiety, which may be extreme
  • Confusion
  • Concentration problems
  • Paranoia
  • Hallucinations and delusions

Additional effects of synthetic cannabinoids, some of which have landed people in the emergency room or intensive care, include:

  • Rapid heart rate and high blood pressure, which can lead to heart attack and stroke
  • Vomiting and other digestive problems
  • Sleepiness
  • Dizziness
  • Muscle damage
  • Violent behavior
  • Thoughts of suicide

The specific effects depend on the specific synthetic product, how much you take, and how long you’ve been using it. So far, doctors don’t know the long-term effects of regular use.

Addiction and Overdose

You can become addicted to synthetic cannabinoids and you can overdose on them. So far, we don’t know what types of addiction counseling and treatment may help people overcome this addiction.

Withdrawal symptoms can include:

  • Headache
  • Nausea and vomiting
  • Severe anxiety
  • Excessive sweating
  • Insomnia
  • Depression
  • Irritability

Symptoms of overdosing on synthetic cannabinoids are:

  • Toxic reactions
  • High blood pressure
  • Chest pain
  • Fast or irregular heart rate
  • Reduced blood supply to the heart
  • Kidney damage
  • Seizures
  • Unexplained bruising
  • Severe bleeding
  • Death

If you or someone you know is displaying these symptoms of overdose after using synthetic cannabinoids, get emergency help right away.

While there’s no specific treatment to reverse the effects of these drugs, treatments such as oxygen, IV fluids, and medication to alleviate specific side effects (seizures, anxiety, heart palpitations) can help.


Many synthetic cannabinoids are against the law. The federal government has passed laws against specific chemical formulations as well as general categories of ingredients. Some states and smaller municipalities have similar laws, as well.

That has not stopped their manufacture and sale, however. To skirt legal penalties, some products are called herbal incense or liquid incense and labeled “not for human consumption.” Many of those that aren’t labeled in this way are also illegal.

The false claim that these products are legal may encourage some people who want to use marijuana, medicinally or legally, to try synthetics. The recent federal legalization of hemp-derived products (such as CBD) and the legalization of marijuana in some states may help confuse this issue and leave people unsure what is and isn’t legal where they live.

It’s important to know the laws where you live and to make sure you’re using products that are not only legal but safe for consumption.

Where They Came From

Originally, synthetic cannabinoids were developed by scientists for studying the endocannabinoid system and as potential new medications. As information about these chemicals became public by scientists sharing information for research purposes, however, the information was “hijacked” by people who then developed them for illicit uses.

In the United States, the first reports of harmful effects from these products came out in 2009 and the problem has continued to intensify ever since. In the first seven months of 2020, poison control centers report fielding 556 calls related to synthetic cannabinoid use.

For several years, scientists working in this field have been calling for more research into the effects of synthetic cannabinoids, how they interact with each other, and what contaminants they typically contain so they can advise lawmakers in how to regulate them and doctors in how to treat people who come into emergency rooms or drug rehab clinics. 

A Word From Verywell

In the end, regardless of their legality or what claims manufacturers make, synthetic cannabinoids are not safe for consumption. If you believe you’re addicted or know someone who may be, it’s important to seek help and stop these dangerous drugs from doing harm.

The first step toward getting help is to talk to your doctor. To find a good drug rehab facility, you can utilize the resources at the Partnership to End Addiction at

Help is also available at the Substance Abuse and Mental Health Services Administration (SAMHSA) National Helpline at 1-800-662-4357.

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Article Sources
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