Kronic

Synthetic cannabinoids are a class of chemicals that are different from the cannabinoids found in cannabis but which also bind to cannabinoid receptors. They are often marketed as designer drugs or sold in products with claims that they give the effects of cannabis. When these chemicals are sprayed or otherwise soaked into a plant or other base material the blend is sometimes misleadingly referred to as synthetic marijuana. These synthetic marijuana products are sold for recreational drug use.

There are several psychoactive artificial cannabinoid families (e.g. AM-xxx, HU-xxx, JWH-xxx, CP xx) that are sprayed onto plant matter that is then sold under brand names like K2 and Spice both of which are now often used as generic terms used for any synthetic cannabis product.

When synthetic cannabinoid blends first went on sale in the early 2000s, it was thought that they achieved an effect through a mixture of natural herbs. Laboratory analysis in 2008 showed that this was not the case, and that many in fact contain synthetic cannabinoids that act on the body in a similar way to cannabinoids naturally found in cannabis, such as THC or CBD. A large and complex variety of synthetic cannabinoids, most often cannabicyclohexanol, JWH-018, JWH-073, or HU-210, are used in an attempt to avoid the laws that make cannabis illegal, making synthetic cannabinoid a designer drug. They have been sold under various brand names, online, in head shops, and other stores. Studies have associated synthetic cannabinoid use with psychotic episodes days after use, some of which have resulted in death.

These blends are often marketed as herbal incense or "herbal smoking blends", and the products are usually consumed through smoking. Although synthetic cannabinoids may not produce positive results in drug tests for cannabis, it is possible to detect their metabolites in human urine. The synthetic cannabinoids contained in these products have been made illegal in many countries.

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