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K2: Synthetic Cannabinoids

K2, also called synthetic cannabinoids, is made of harmful chemicals designed to act on the same brain receptors as THC, the main active component in cannabis. However, K2 is not the same as cannabis and has different effects. These harmful chemicals are typically sprayed onto dried plant material and sold in colorful packaging.

They are often misleadingly labeled as "herbal incense" or “not for human consumption,” even though they are commonly smoked, vaped, or ingested for their psychoactive effects.

Consuming K2 can lead to serious and unpredictable health risks, including death.

Reasons People Use K2

​​​People may use K2 for several reasons, including:

  • ​K2 is usually cheaper and more accessible than other drugs. ​​
  • ​K2 is fast-acting and often highly potent.
  • ​​​K2 does not show up on standard toxicology tests used commonly in health care, criminal justice, probation, shelter, or correctional settings.
  • K2 may be used to cope with emotional pain, trauma, or the effects of other mental or physical health conditions, similar to alcohol and other substances.

How K2 Is Commonly Used

K2 is most often smoked by rolling it in smoking paper (to make a joint) or using pipes. It can also be smoked in bongs or inhaled from makeshift devices. The effects are typically felt within minutes and may last from one to six hours.

Health Risks

K2 use can cause a wide range of serious health issues, including death. Examples include the following:

  • Short term symptoms such as agitation, confusion, hallucinations, paranoia, vomiting, rapid heart rate, and high blood pressure
  • Serious medical complications, even after a single use
    • These include chest pain, difficulty breathing, kidney failure, seizures, and stroke. These effects may happen suddenly and require emergency medical attention.
  • Psychological effects such as delusions, suicidal thoughts, and violent behavior
  • Withdrawal symptoms after long-term use
    • These may involve headaches, anxiety, nausea, sweating, insomnia, rapid heart rate, and seizures.

Information for Providers

Diagnosing K2-related illness is difficult. Symptoms can mimic psychiatric or neurological conditions, and reactions vary widely. Additionally, the chemical formulations of K2 are constantly changing, making the effects hard to predict. Clinicians should observe and treat the symptoms that are present.

Toxicology testing is not a reliable way to identify or reduce the harms of K2 use. There is no standard toxicology screen that reliably detects synthetic cannabinoids, and patients may not always disclose their K2 use.

Additional Resources