Marijuana, also known as cannabis and a host of other names, is a drug that has been around since at least the third millennium BC. The word marijuana typically refers to the dried preparation of the cannabis indica or cannabis sativa plant, which can be smoked or ingested. Cannabis indica and sativa are native to Central and South Asia, and is believed to have originated in the Himalayas. It has an ancient history of ritual use, marijuana traces having been found in many burial sites and excavations around the world. Traces of marijuana were even found in pipes on what is believed to have been William Shakespeare's property in Stratford upon Avon, in England!
The main psychoactive compound in marijuana is THC, or tetrahydrocannibinol, which is mainly responsible for the "high" that marijuana use produces. However, there are at least sixty six other cannabinoids found in marijuana, with the major three being CBD, CBN, and THVC. CBD acts as a sedative in animal tests, and is the major ingredient in several medical marijuana alternatives. CBN is a psychedelic, and THVC is receptor antagonist which may be used as a treatment for type-2 diabetes. Based on a combination of these compounds, the high the marijuana user experiences differs greatly, from a "heady" and alert high to a stuck on the couch "stoned". One may hear long time marijuana users talking (or complaining) about the potency of the newer strains of marijuana, and indeed, average THC concentrations have increased from 4% in 1983 to 9.6% in 2007, with high class marijuana strains reaching or surpassing 20% THC content.
Marijuana comes in many different forms and is delivered to the brain in a variety of different ways. The term marijuana refers to the dried buds or flowers and their immediate attendant leaves, with the large fan leaves and stems removed. Hasish is a resin that is made from the flowers of the female cannibis plant, but can also be made from the leftover cuttings of a marijuana harvest. Hashish, or simply hash, has a higher average THC content than regular marijuana but has also been found to be adulterated or cut with many other harmful substances, as dealers try to increase the apparent amount of sticky black hasish with even feces. Hash oil is usually a light golden liquid extracted from the non-essential parts the of the marijuana plant using solvents in a sometimes dangerous process, and it may have up to a 90% cannaniniod makeup. Keif is a white or yellow powder made from the loose crystals (trichomes) that fall off the mature flowers.
All of the above marijuana preparations can be smoked, in a pipe (usually glass), a joint (rolled marijuana cigarette), a bong (water filtered pipe), or a vaporizer, which heats the marijuana to the precise temperature at which THC is vaporized, leaving the rest of the potentially harmful plant materials alone. Hash oil and keif are usually put on top of regular marijuana to enhance the experience.
Marijuana is mainly classified as a hallucinogenic, but also exhibits the properties of both stimulants and depressants and as such defies any hard classification. While a New Zealand study has found a 5.7% greater risk of lung cancer for marijuana smokers, other studies find no correlation or even that smoking cannabis reduces the risk of lung, neck, and cranial cancers. Marijuana use has also been correlated with an increased risk for psychotic disorders, though the debate rages as to whether this correlation is causal or not. FMRI studies show a change in neurological patterns in heavy marijuana users, though these patterns to revert to normal activity after a period of abstinence. Chronic marijuana users also exhibit impaired psychomotor skills, such as slow reaction times, drowsiness, being less concentrated, impaired motor skills, and making more mistakes during performance testing. High potency marijuana can remain in ones system for up to eight hours after smoking a single joint, and reaction times can be impaired for up to five hours. Short term memory can also be impaired.
While it is classified as one of the least dangerous and most widely used illegal drugs, marijuana still has the potential for psychological dependence. Frequent obsession with marijuana, disproportionate time spent using and searching for a supply, use at the expense of other areas of life, or use in face of consequences are all signs of marijuana addiction. When people say, as many do, that marijuana is not addictive, what they really mean is that it is not physically addictive. However, the psychological addiction is very real and follows the same modus operandi as an addiction to heroin, alcohol, overeating, or gambling, and can lead down a very dark path of failure and social withdrawal.