Spice is an herbal substance which has also been called K2 or fake marijuana. People report many similarities to marijuana, including the production of euphoria, feeling calm, perceptual distortions, rapid heart rate, and hallucinations. It is usually smoked.
The herbal mixture created is sometimes found to have additional synthetic compounds which bind strongly to the natural cannabinoid receptors in the brain. It is still unknown what the exact nature of these compounds are and their complete effects in humans. At present, Spice has been made illegal to possess or sell in many states.
Some people who become dependent experience a withdrawal syndrome that resembles that of cannabis dependence. Upon abrupt discontinuation, one may feel anxious, tense, irritable, and have intense craving, sleep disturbance, and impaired concentration. As of yet, there is no known specific treatment for this syndrome.
It is only recently that laboratories have developed specific assays to detect Spice in the urine.