Cannabis, commonly known in some regions as Marijuana, and by various colloquial names, refers to a genus of plants indigenous to Central and South Asia. The genus is scientifically subdivided into three species, Ruderalis, Indica and Sativa, however there is little scientific consensus on taxonomy and often little correlation between scientific classification and commercial descriptions of strains as 'Sativa' or 'Indica'. Commercial psychoactive strains of Cannabis are typically hybrids of Sativa, Indica and/or Ruderalis.
Whilst the Cannabis plant has various uses in production of fibres, it is most well known today for its psychoactive effects. Various desirable sensations are reported in individuals who have consumed cannabis, such as euphoria, relaxation, and sleepiness. Adverse effects include decreased short term memory, dryness of the oral cavity ("Cotton-mouth"), impaired motor skills and reddening of the eyes. Occasionally, cannabis can produce anxiety, panic, or paranoia. Rarely, cannabis has been implicated in the development of acute psychosis. A full range of effects can be found on the Tripsit Factsheets.
The primary psychoactive agent in cannabis is believed to be tetrahydrocannabinol, however the drug contains at least 65 other cannabinoids, and 485 compounds have been identified thus far in cannabis. The extent to which these compounds produce psychoactive effects is a matter of ongoing research.
Cannabis can be consumed in a variety of ways, such as smoking, vaporisation, consumption as part of foods and in extracts. 
Cannabis has been used throughout history as both a recreational drug, medicine and spiritual aid. 128 to 232 million people used cannabis (2.7% to 4.9% of the global population between the ages of 15 and 65) in 2013, making it the most commonly used illicit drug on Earth.
In recent times there have been developments in the legal use of cannabis as a medication for various ailments. Canada, Belgium, Australia, the Netherlands, Spain, and 23 U.S. states have made medicinal cannabis usage legal. 
The word 'Cannabis' appears to derive from the Greek 'kannabis', a loanword from Scythia or Thrace, where it was used to refer to the hemp plant. It has been in use in English to refer to 'common hemp', the variant of the plant used to create fibres, from 1798, and in reference to the psychoactive usage of the plant from 1848. It may have provided the origin for the words 'hemp' and 'canvas'.
Evidence of cannabis cultivation dates back to 4000BCE, in China, where it was used for the manufacture of strings, ropes, textiles, paper and food. The earliest known pharmacopoeia, pen-ts'ao ching (Classic of Herbal Medicine) describes medical use of the cannabis plant, which may date as as far back as 2800 BCE. 
This text also states:
...ma-fen (the fruit of cannabis)... if taken in excess will produce visions of devils … over a long term, it makes one communicate with spirits and lightens one's body…
But Chinese texts otherwise rarely refer to its psychoactive effects.
In India cannabis usage has been widespread for thousands of years, being entwined with recreational usage, medicinal treatments and religious ritual. The Atharvaveda, an ancient text of Hinduism dating back at least 2000 years describes cannabis as one of five sacred plants. Medicinal and religious usage of cannabis likely dates back at least 3000 years.
Cannabis first appears in ancient western literature in the account of the 5th century BCE Geek historian Heterodotus, who described a practice of burning hemp to release vapour practised by ancient Scythians. This has been corroborated by the discovery of charred cannabis seeds in Scythian tombs. 
Whilst evidence of Roman usage of cannabis medicinally is sparse, Greek accounts exist of cannabis being used to treat a number of ailments, such as salves for wounds in horses, tinctures used to treat inflammation in the ears and the consumption of various parts of the plant for treatment of nosebleeds and even tapeworms.
Recreational consumption of Cannabis is described as early as the 4th century BCE by Ephippus, and also by the famed physician Galen in the 2nd century CE, however it does not appear to have been widely used.
By the beginning of second millennium cannabis began to spread from Central and South Asia to Arabia, appearing in Arabic documents from the period, and by the 16th century was widespread throughout Africa and areas of the Americas in contact with Europeans.
In the Americas the cannabis plant was widely cultivated, and its domestic production encouraged in the United states from 1600 to the 19th century, where it was used for textile and rope production. The 1619 Virginia Assembly made hemp growing mandatory for all farmers in the colony, and hemp was even traded as legal tender in Pennsylvania, Virginia and Maryland.
The first country to outlaw the use of cannabis was South Africa in 1911, followed by Jamaica in 1913, potentially as methods of controlling the non-White population. Canada, the United Kingdom and New Zealand all illegalised cannabis in the 1920s, as part of a wider programme of banning psychoactives such as opium. Canada appears to have banned the drug several years before any reported use of the drug in the country.
By the 1930s a campaign to criminalise cannabis had developed in the United States. Playing on racism, xenophobia and general ignorance about the drug amongst the population, newspapers filled with editorialised accounts of 'reefer madness' and links between Cannabis and crime, often associated with the Black and Mexican communities.  Around this time the word 'Marijuana', previously uncommon outside of a few Mexican communities became popularised by the anti-cannabis movement in a bid to make it appear foreign, strange and exotic
By 1933 30 US states had some form of legislation against cannabis. Throughout the 1930s the head of the Federal Bureau of Narcotics, Henry Anslinger successfully campaigned for the illegalisation of cannabis, associating it with violence, corruption of white american young people by immigrants and Blacks and other polemics which played on the fears of white America. By 1937 a federal $100-per ounce tax on cannabis cultivation effectively banned the plant nationwide.
Hemp is the natural, durable soft fiber from the stalk of Cannabis sativa plants that grow upwards of 20 feet tall. Cannabis plants used for hemp production are not valued for recreational uses as the plants that are cultivated for hemp produce minimal levels of THCTetrahydrocannabinol, analogous to attempting to get drunk from low-alcohol beer. Cannabis plants intended for any drug cultivation cannot be hidden in a hemp field either, as the size and height of each are significantly different.
Hemp producers sell hemp seeds as a health food, as they are rich in heart-healthy, essential fatty acids, amino acids (both essential and nonessential), vitamins and minerals. Hemp "milk" is a milk substitute also made from hemp seeds that is both dairy and gluten-free.
Hemp is fairly easy to grow and matures very fast compared to many crops, most notably trees used for paper. Compared to cotton for clothing, hemp cloth is known to be of superior strength and longer-lasting. The fibers may also be used to form cordage for industrial-strength ropes. Hemp plants also require little pesticides and herbicides due to its height, density and foliage. This also makes the hemp plant very environmentally-friendly.
Hemp can be utilized for 25,000 very durable textile products, ranging from paper and clothing to biofuels (from the oils found in the seeds), medicines and construction material. Hemp has been used by many civilizations, from China to Europe (and later North America) for the last 12,000 years of history. Recreational use Comparison of physical harm and dependence regarding various drugs (the British medical journal The Lancet). Main article: Cannabis (drug) See also: Tetrahydrocannabinol, Cannabidiol, and Effects of cannabis
Cannabis is a popular recreational drug around the world, only behind alcohol, caffeine and tobacco. In the United States alone, it is believed that over 100 million Americans have tried Cannabis, with 25 million Americans using it within the past year.
The psychoactive effects of Cannabis are known to have a biphasic nature. Primary psychoactive effects include a state of relaxation, and to a lesser degree, euphoria from its main psychoactive compound, tetrahydrocannabinol. Secondary psychoactive effects, such as a facility for philosophical thinking; introspection and metacognition have been reported, amongst cases of anxiety and paranoia. Finally, the tertiary psychoactive effects of the drug cannabis, can include an increase in heart rate and hunger, believed to be caused by 11-Hydroxy-THCTetrahydrocannabinol, a psychoactive metabolite of THCTetrahydrocannabinol produced in the liver.
Normal cognition is restored after approximately three hours for larger doses via a smoking pipe, bong or vaporizer. However, if a large amount is taken orallyRoute of administration in which the subject swallows a substance. the effects may last much longer. After 24 hours to a few days, minuscule psychoactive effects may be felt, depending on dosage, frequency and tolerance to the drug.
Various forms of the drug cannabis exist, including extracts such as hashish and hash oil which, due to appearance, are more susceptible to adulterants when left unregulated.
The plant Cannabis sativa is known to cause more of a "high" by stimulating hunger and by producing a rather more comedic, or energetic feeling. Conversely, the Cannabis indica plant is known to cause more of a "stoned" type of feeling, possibly due to a higher CBDCannabidiol to THCTetrahydrocannabinol ratio.
Cannabidiol (CBDCannabidiol), which has no psychotropic effects by itself] (although sometimes showing a small stimulant effect, similar to caffeine), attenuates, or reduces the higher anxiety levels caused by THCTetrahydrocannabinol alone.
According to the UK medical journal The Lancet, Cannabis has a lower rate of dependence compared to both nicotine and alcohol. However, everyday use of Cannabis can in some cases, be correlated with some psychological withdrawal symptoms such as irritability, and insomnia and evidence could suggest that if a user experiences stress, the likeliness of getting a panic attack increases due to an increase of THCTetrahydrocannabinol metabolites. However, any Cannabis withdrawal symptoms are typically mild and are never life-threatening.
A synthetic form of the main psychoactive cannabinoidChemicals produced naturally that bind to cannabinoid receptors. They are involved in a variety of mental and physical processes, including pain regulation, food intake, and reward. in Cannabis, Δ9-tetrahydrocannabinol (THCTetrahydrocannabinol), is used as a treatment for a wide range of medical conditions.
In the United States, although the Food and Drug Administration (FDA) does acknowledge that "there has been considerable interest in its use for the treatment of a number of conditions, including glaucoma, AIDS wasting, neuropathic pain, treatment of spasticity associated with multiple sclerosis, and chemotherapy-induced nausea," the agency has not approved "medical marijuana". There are currently 2 oral forms of cannabis (cannabinoids) available by prescription in the United States for nausea and vomiting associated with cancer chemotherapy: dronabinol (Marinol) and nabilone (Cesamet). Dronabinol is also approved for the treatment of anorexia associated with AIDS. The FDA does facilitate scientific investigations into the medical uses of cannabinoids.
In a collection of writings on medical marijuana by 45 researchers, a literature review on the medicinal uses of Cannabis and cannabinoids concluded that established uses include easing of nausea and vomiting, anorexia, and weight loss; "well-confirmed effect" was found in the treatment of spasticity, painful conditions (i.e. neurogenic pain), movement disorders, asthma, and glaucoma. Reported but "less-confirmed" effects included treatment of allergies, inflammation, infection, epilepsy, depression, bipolar disorders, anxiety disorder, dependency and withdrawal. Basic level research was being carried out at the time on autoimmune disease, cancer, neuroprotection, fever, disorders of blood pressure.
Clinical trials conducted by the American Marijuana Policy Project, have shown the efficacy of cannabis as a treatment for cancer and AIDS patients, who often suffer from clinical depression, and from nausea and resulting weight loss due to chemotherapy and other aggressive treatments. A synthetic version of the cannabinoidChemicals produced naturally that bind to cannabinoid receptors. They are involved in a variety of mental and physical processes, including pain regulation, food intake, and reward. THCTetrahydrocannabinol named dronabinol has been shown to relieve symptoms of anorexia and reduce agitation in elderly Alzheimer's patients. Dronabinol has been approved for use with anorexia in patients with HIV/AIDS and chemotherapy-related nausea. This drug, while demonstrating the effectiveness of Cannabis at combating several disorders, is more expensive and less available than whole cannabis and has not been shown to be effective or safe.
Glaucoma, a condition of increased pressure within the eyeball causing gradual loss of sight, can be treated with medical marijuana to decrease this intraocular pressure. There has been debate for 25 years on the subject. Some studies have shown a reduction of IOP in glaucoma patients who smoke cannabis, but the effects are generally short-lived. There exists some concern over its use since it can also decrease blood flow to the optic nerve. Marijuana lowers IOP by acting on a cannabinoidChemicals produced naturally that bind to cannabinoid receptors. They are involved in a variety of mental and physical processes, including pain regulation, food intake, and reward. receptor on the ciliary body called the CB receptor. Although Cannabis may not be the best therapeutic choice for glaucoma patients, it may lead researchers to more effective treatments. A promising study shows that agents targeted to ocular CB receptors can reduce IOP in glaucoma patients who have failed other therapies.
Medical cannabis is also used for analgesia, or pain relief. It is also reported to be beneficial for treating certain neurological illnesses such as epilepsy, and bipolar disorder. Case reports have found that Cannabis can relieve tics in people with obsessive compulsive disorder and Tourette syndrome. Patients treated with tetrahydrocannabinol, the main psychoactive chemical found in Cannabis, reported a significant decrease in both motor and vocal tics, some of 50% or more. Some decrease in obsessive-compulsive behavior was also found. A recent study has also concluded that cannabinoids found in Cannabis might have the ability to prevent Alzheimer's disease. THCTetrahydrocannabinol has been shown to reduce arterial blockages.
Another potential use for medical cannabis is movement disorders. Cannabis is frequently reported to reduce the muscle spasms associated with multiple sclerosis; this has been acknowledged by the Institute of Medicine, but it noted that these abundant anecdotal reports are not well-supported by clinical data. Evidence from animal studies suggests that there is a possible role for cannabinoids in the treatment of certain types of epileptic seizures. A synthetic version of the major active compound in Cannabis, THCTetrahydrocannabinol, is available in capsule form as the prescription drug dronabinol (Marinol) in many countries. The prescription drug Sativex, an extract of cannabis administered as a sublingual spray, has been approved in Canada for the treatment of multiple sclerosis.
Cannabis is first referred to in Hindu Vedas between 2000 and 1400 BCE, in the Atharvaveda. By the 10 century CE, it was being referred to in India as "food of the gods". Cannabis use eventually became a ritual part of the Hindu festival of Holi. In Buddhism, cannabis has been used in meditation and regarded as a holy plant since 500 BCE. Shamanic use of Cannabis in China has been dated to at least 1000 BCE. In ancient Germanic culture, Cannabis was associated with the Norse love goddess, Freya. An anointing oil mentioned in Exodus is, by some translators, said to contain Cannabis. Sufis have used Cannabis in a spiritual context since the thirteenth century CE.
In modern times the Rastafari movement has embraced Cannabis as a sacrament. Elders of the modern religious movement known as the Ethiopian Zion Coptic Church consider Cannabis to be the Eucharist, claiming it as an oral tradition from Ethiopia dating back to the time of Christ, even though the movement was founded in the United States in 1975 and has no ties to either Ethiopia or the Coptic Church. Like the Rastafari, some modern Gnostic Christian sects have asserted that Cannabis is the Tree of Life. Other organized religions founded in the 20th century that treat Cannabis as a sacrament are the THCTetrahydrocannabinol Ministry, the Way of Infinite Harmony, Cantheism, the Cannabis Assembly and the Church of Cognizance.
Cannabis field seized by authorities.
Dosages from TripSit Factsheets
CannabinoidChemicals produced naturally that bind to cannabinoid receptors. They are involved in a variety of mental and physical processes, including pain regulation, food intake, and reward. research chemicals receive relatively frequent media coverage in cases of overdoses. This is generally because cannabinoids are often sold in blends without dosing information or sometimes even the active component - if you are looking to take cannabinoids in an informed manner, blends should be avoided unless accurate information is provided alongside it. When cannabinoids are bought in pure form, they are often active in the microgram range, and can be quite difficult to measure.
Overdoses of cannabinoids are generally known to cause hallucinatory experiences, which in turn often cause panic attacks. Larger overdoses may also cause heart issues. Repetitive heavy dosing of certain cannabinoids are suspected to cause organ damage.
See Research Chemicals for more information.
Both Cannabis and Tetrahydrocannabinols, the active chemicals contained in Cannabis plants, are Schedule I in the United States. This means they are federally illegal to cultivate, buy, possess, or distribute (sell, trade or give) in all forms (cannabis plants, extracts, hash, hash oil, thc, etc) except synthetic THCTetrahydrocannabinol (Marinol) which is Schedule III.
Practically, simple possession of small amounts is almost never prosecuted federally.
The federal scheduling of Cannabis was disputed in 1988 by Judge Francis Young, an administrative law judge for the DEA, who recommended that marijuana be reclassified as schedule II on the grounds that if a respectable minority of doctors endorse it, then it has a "currently accepted medical use".
Cannabis has many reported medical uses and its active component is an approved drug in the US. The US government has, in the last 20 years, been forced to provide medical cannabis to 8 patients in the form of cannabis cigarettes although as a top level, federal policy has opposed any change in the status of cannabis to move it to a lower schedule. Over a dozen states now allow some provision for the medical use of cannabis, although only around 8 have effective protection (AK, CA, CO, HI, ME, NV, OR, WA).
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