Cannabis, also known as marijuana<ref>See, Etymology of marijuana.</ref>, marihuana,<ref name="bookSpanish Word Histories or and Mysteries">Template:Cite book</ref> and ganja (from Template:Lang-sa gañjā, meaning "hemp"), among many other namesTemplate:Cref, refers to any number of preparations of the Cannabis plant intended for use as a psychoactive drug. The most common form of cannabis used as a drug is the dried herbal form.

The typical herbal form of cannabis consists of the flowers and subtending leaves and stalks of mature pistillate or female plants. The resinous form of the drug is known as hashish (or merely as 'hash').<ref name="urlTypes of Cannabis Available in the United Kingdom">Template:Cite web</ref>

The major psychoactive chemical compound in cannabis is Δ<sup>9</sup>-tetrahydrocannabinol (commonly abbreviated as THC). At least 66 other cannabinoids are also present in cannabis, including cannabidiol (CBD), cannabinol (CBN) and tetrahydrocannabivarin (THCV) among many others, which are believed in influence the effects of THC alone.<ref name="pmid19124693">{{cite journal
|author=Fusar-Poli P, Crippa JA, Bhattacharyya S, et al.
|title=Distinct effects of {delta}9-tetrahydrocannabinol and cannabidiol on neural activation during emotional processing
|journal=Archives of General Psychiatry

Cannabis use has been found to have occurred as long ago as the third millennium B.C.<ref name="bookLost Civilisations of the Stone Age">Template:Cite book</ref> In modern times, the drug has been used for recreational, religious or spiritual, and medicinal purposes. The United Nations (UN) estimated that in 2004 about 4% of the world's adult population (162 million people) use cannabis annually, and about 0.6% (22.5 million) use it on a daily basis.<ref name="articleUnited Nations Office on Drugs and Crime">Template:Citation</ref> The possession, use, or sale of cannabis preparations containing psychoactive cannabinoids became illegal in most parts of the world in the early twentieth century. Since then, some countries have intensified the enforcement of cannabis prohibition, while others have reduced it.

== History ==

Cannabis is indigenous to Central and South Asia.<ref>"Marijuana and the Cannabinoids", ElSohly(p.8)</ref> Evidence of the inhalation of cannabis smoke can be found as far back as the 3rd millennium B.C., as indicated by charred cannabis seeds found in a ritual brazier at an ancient burial site in present day Romania.<ref name="bookLost Civilisations of the Stone Age"/> Cannabis is also known to have been used by the ancient Hindus of India and Nepal thousands of years ago. The herb was called ganjika in Sanskrit (गांजा/গাঁজা ganja in modern Indic languages).<ref name="bookFlashbacks">Template:Cite book</ref><ref name="pmid17759460">Template:Cite book.</ref> The ancient drug soma, mentioned in the Vedas as a sacred intoxicating hallucinogen, was sometimes associated with cannabis.<ref name="bookThe Encyclopedia of Psychoactive Substances">Template:Cite book</ref>

Cannabis was also known to the ancient Assyrians, who discovered its psychoactive properties through the Aryans.<ref>Template:Cite book p. 3.</ref> Using it in some religious ceremonies, they called it qunubu (meaning "way to produce smoke"), a probable origin of the modern word "cannabis".<ref>Template:Cite book p. 305.</ref> Cannabis was also introduced by the Aryans to the Scythians and Thracians/Dacians, whose shamans (the kapnobatai—"those who walk on smoke/clouds") burned cannabis flowers to induce a state of trance.<ref>Template:Cite book p. 405.</ref> Members of the cult of Dionysus, believed to have originated in Thrace (Bulgaria, Greece and Turkey), are also thought to have inhaled cannabis smoke. In 2003, a leather basket filled with cannabis leaf fragments and seeds was found next to a 2,500- to 2,800-year-old mummified shaman in the northwestern Xinjiang Uygur Autonomous Region of China.<ref name="peoplesdaily">Template:Cite web</ref><ref name="jiang2006a">Template:Cite journal</ref>


Cannabis has an ancient history of ritual use and is found in pharmacological cults around the world. Hemp seeds discovered by archaeologists at Pazyryk suggest early ceremonial practices like eating by the Scythians occurred during the 5th to 2nd century B.C., confirming previous historical reports by Herodotus.<ref>Template:Cite book p. 6.</ref> One writer has claimed that cannabis was used as a religious sacrament by ancient Jews and early Christians<ref>Template:Cite web</ref> due to the similarity between the Hebrew word "qannabbos" ("cannabis") and the Hebrew phrase "qené bósem" ("aromatic cane"). It was used by Muslims in various Sufi orders as early as the Mamluk period, for example by the Qalandars.<ref>Template:Cite book</ref>

A study published in the South African Journal of Science showed that "pipes dug up from the garden of Shakespeare's home in Stratford upon Avon contain traces of cannabis."<ref name='Shakespeare-BBC-2001'>Template:Cite news</ref> The chemical analysis was carried out after researchers hypothesized that the "noted weed" mentioned in Sonnet 76 and the "journey in my head" from Sonnet 27 could be references to cannabis and the use thereof.<ref name='Shakespeare-CNN-2001'>Template:Cite news</ref>

Cannabis was criminalized in the United States in 1937 due to Marihuana Tax Act of 1937. Several theories try to explain why it is illegal in most Western societies. Jack Herer, a cannabis legalization activist and writer, argues that the economic interests of the paper and chemical industry were a driving force to make it illegal.<ref>Marijuana Conspiracy - by Dough Yurchey.<!-- Bot generated title --></ref><ref>William Randolf Hearst, Lammont Dupont, Henry J. Anslinger, and hemp [Archive -<!-- Bot generated title -->].</ref><ref><</ref> Another explanation is that beneficial effects of hemp would lower the profit of pharmaceutical companies which therefore have a vital interest to keep cannabis illegal.<ref name="urlCure Cancer with Hemp Oil - Phoenix Tears">Template:Cite web</ref> Those economic theories were criticized for not taking social aspect into account. The illegalization was rather a result of racism directed to associate American immigrants of Mexican and African descent with cannabis abuse.<ref name="urlDebunking the Hemp Conspiracy Theory | DrugReporter | AlterNet">Template:Cite web</ref>

== Forms ==
=== Cannabis (herbal form) ===
File:Bubba Kush.jpg

The terms cannabis or marijuana generally refer to the dried flowers and subtending leaves and stems of the female cannabis plant.  This is the most widely consumed form, containing 3% to 22% THC.<ref></ref><ref>Template:Cite web</ref> In contrast, cannabis strains used to produce industrial hemp contain less than 1% THC and are thus not valued for recreational use.<ref></ref>

=== Hashish ===

Main article: Hashish
Hashish (also spelled hasheesh) or hash is a concentrated resin produced from the flowers of the female cannabis plant. Hash is more potent than marijuana and can be smoked or chewed.<ref name="urlHashish - Definitions from">Template:Cite web</ref> It varies in color from black to golden brown depending upon purity.

=== Hash oil ===

Main article: Hash oil
Hash oil, or honey oil, is an essential oil extracted from the cannabis plant through the use of various solvents. It has a high proportion of cannabinoids (ranging from 40-90%).<ref name="urlHash Oil Info">Template:Cite web</ref> This oil is also used in the process of making a variety of cannabis foods.

=== Kief ===

Main article: Kief
Kief is a powder made from trichomes removed from the leaves and flowers of cannabis plants. Kief can also be compressed to produce one form of hashish, or consumed in powder form.<ref></ref>

=== Resin ===


Main article: Cannabis (hashish) rosin

Because of THC's adhesive properties, resin builds up inside the paraphernalia when cannabis is smoked. It has tar-like properties but still contains THC as well as other cannabinoids. This resin still has all the psychoactive properties of cannabis but is more difficult to smoke due to the discomfort caused to the throat and lungs. Cannabis users typically only smoke resin when cannabis is unavailable. Glass may be water-steamed at a low temperature prior to scraping in order to make the resin easier to remove.<ref name="Pipe Residue Information">Template:Cite web</ref>

== Potency ==
According to the United Nations Office on Drugs and Crime (UNODC), "the amount of THC present in a cannabis sample is generally used as a measure of cannabis potency."<ref name="urlWhy Does Cannabis Potency Matter?">Template:Cite web</ref> The three main forms of cannabis products are the herb (marijuana), resin (hashish), and oil (hash oil). The UNODC states that marijuana often contains 5% THC content, resin "can contain up to 20% THC content", and that "Cannabis oil may contain more than 60% THC content."<ref name="urlWhy Does Cannabis Potency Matter?"/>

A scientific study published in 2000 in the Journal of Forensic Sciences (JFS) found that the potency (THC content) of confiscated cannabis in the United States (US) rose from "approximately 3.3% in 1983 and 1984", to "4.47% in 1997". It also concluded that "other major cannabinoids (i.e., CBD, CBN, and CBC)" (other chemicals in cannabis) "showed no significant change in their concentration over the years".<ref name="pmid10641915">Template:Cite journal</ref>. More recent research undertaken at the University of Mississippi's Potency Monitoring Project<ref></ref> has found that average THC levels in cannabis samples between 1975 and 2007 have increased from 4% in 1983 to 9.6% in 2007.

Australia's National Cannabis Prevention and Information Centre (NCPIC) states that the buds (flowers) of the female cannabis plant contain the highest concentration of THC, followed by the leaves. The stalks and seeds have "much lower THC levels".<ref name="urlCannabis Potency">Template:Cite web</ref> The UN states that the leaves can contain ten times less THC than the buds, and the stalks one hundred times less THC.<ref name="urlWhy Does Cannabis Potency Matter?"/>

== Routes of administration ==

<!--***PLEASE do not add any more detail to this section. Development is more than welcome at Cannabis consumption. THANKS! -->
File:Volcano Vaporizer.jpg

File:Joint and smoke.jpg


Main article: Cannabis consumption

Cannabis is consumed in many different ways, most of which involve inhaling smoke.

The most commonly used include screened bowls, bubblers (small pipes with water chambers), bongs, one-hitters, chillums, paper-wrapped joints and tobacco-leaf-wrapped blunts. Local methods differ by the preparation of the cannabis plant before use, the parts of the cannabis plant which are used, and the treatment of the smoke before inhalation.

A vaporizer heats herbal cannabis to 365–410 °F (185–210 °C), which causes the active ingredients to evaporate into a gas without burning the plant material (the boiling point of THC is 392°F (200°C) at 0.02mmHg pressure, and somewhat higher at standard atmospheric pressure).<ref name="merck1989">1989. The Merck Index, 11th ed., Merck & Co., Rahway, New Jersey.</ref> A lower proportion of toxic chemicals are released than by smoking, although this may vary depending on the design of the vaporizer and the temperature at which it is set. This method of consuming cannabis produces markedly different effects than smoking due to the flash points of different cannabinoids; for example, CBN has a flash point of 212.7°C<ref name="urlChemSpider - Cannabinol">Template:Cite web</ref> and would normally be present in smoke but might not be present in vapor.

As an alternative to smoking, cannabis may be consumed orally. However, the cannabis or its extract must be sufficiently heated or dehydrated to cause decarboxylation of its most abundant cannabinoid, tetrahydrocannabinolic acid (THCA), into psychoactive THC.<ref name="urlDecarboxylation - Does Marijuana Have to be Heated to Become Psychoactive?">Template:Cite web</ref>

Cannabinoids can be leached from cannabis plant matter using high-proof spirits (often grain alcohol) to create a tincture, often referred to as Green Dragon.

Cannabis can also be consumed as a tea. THC is lipophilic and only slightly water soluble (with a solubility of 2.8 mg per liter),<ref name="Physical Properties - Dronabinol">Template:Cite web</ref> so tea is made by first adding a saturated fat to hot water (i.e. cream or any milk except skim) with a small amount of cannabis, green or black tea leaves and honey or sugar, steeped for approximately 5 minutes.

== Effects ==

<!--***PLEASE, do not add more detail to this section, contributions are more than welcome at Effects of cannabis. THANKS. -->
File:Bodily effects of cannabis.png

Main article: Effects of cannabis

Cannabis has psychoactive and physiological effects when consumed. The minimum amount of THC required to have a perceptible psychoactive effect is about 10 micrograms per kilogram of body weight.<ref name="The Tolerance Factor">Template:Cite web</ref> Aside from a subjective change in perception, the most common short-term physical and neurological effects include increased heart rate, lowered blood pressure, impairment of short-term episodic memory, working memory, psychomotor coordination, and concentration.<ref name=memoryhindered>Template:Cite journal</ref> Long-term effects are less clear.<ref>Long-Term Effects of Exposure to Cannabis.</ref><ref>Adverse Effects of Cannabis on Health: An Update of the Literature Since 1996.</ref>

=== Classification ===

Main article: Effects of cannabis#Psychoactive effects

While many drugs clearly fall into the category of either stimulant, depressant, or hallucinogen, cannabis exhibits a mix of all properties, perhaps leaning the most towards hallucinogen or psychedelic properties, though with other effects quite pronounced as well. Though THC is typically considered the primary active component of the cannabis plant, various scientific studies have suggested that certain other cannabinoids like CBD may also play a significant role in its psychoactive effects.<ref name="bookDrugs and Behavior: An Introduction to Behavioral Pharmacology (5th Edition)">Template:Cite book</ref><ref name="urlInformation on Drugs of Abuse">Template:Cite web</ref><ref name="bookPsychedelics Encyclopedia">Template:Cite book</ref>

<!-- === Health issues ===

 This section is designed to be a summary of the health issues presented in the "Effects of Cannabis" article. Add all other info, including specific studies to Effects of Cannabis-->

=== Medical use ===

Main article: Medical cannabis

Although the extent of the medicinal value of cannabis has been debated, it does have several well-documented beneficial effects. Among these are: the amelioration of nausea and vomiting, stimulation of hunger in chemotherapy and AIDS patients, lowered intraocular eye pressure (shown to be effective for treating glaucoma), as well as general analgesic effects (pain reliever).Template:Cref

Less confirmed individual studies also have been conducted indicating cannabis to be beneficial to a gamut of conditions running from multiple sclerosis to depression. Synthesized cannabinoids are also sold as prescription drugs, including Marinol (dronabinol in the United States and Germany) and Cesamet (nabilone in Canada, Mexico, The United States and The United Kingdom).Template:Cref

Currently, the U.S. Food and Drug Administration (FDA) has not approved smoked marijuana for any condition or disease in the United States. Regardless, thirteen states have legalized cannabis for medical use.<ref></ref><ref>FDA: Inter-Agency Advisory Regarding Claims That Smoked Marijuana Is a Medicine</ref> Canada, Spain, The Netherlands and Austria have also legalized cannabis for medicinal use.<ref></ref><ref></ref>

=== Long-term effects ===

Main article: Effects of cannabis#Long-term effects

The smoking of cannabis is the most harmful method of consumption, as the inhalation of smoke from organic materials can cause various health problems.<ref name="journalHarm Reduction Associated with Inhalation and Oral Administration of Cannabis and THC">Template:Cite journal</ref>

By comparison, studies on the vaporization of cannabis found that subjects were "only 40% as likely to report respiratory symptoms as users who do not vaporize, even when age, sex, cigarette use, and amount of cannabis consumed are controlled."<ref name="pmid17437626">Template:Cite journal</ref> Another study found vaporizers to be "a safe and effective cannabinoid delivery system."<ref name="pmid17429350">Template:Cite journal</ref><ref name="pmid16637053">Template:Cite journal</ref>

File:Rational scale to assess the harm of drugs (mean physical harm and mean dependence).svg

While a study in New Zealand of 79 lung-cancer patients suggested daily cannabis smokers have a 5.7 times higher risk of lung cancer than non-users,<ref>Template:Cite web</ref> another study of 2252 people in Los Angeles failed to find a correlation between the smoking of cannabis and lung, head or neck cancers.<ref name="Study Finds No Link Between Marijuana Use And Lung Cancer">Template:Cite news</ref>  These effects have been attributed to the well documented anti-tumoral properties of cannabinoids, specifically tetrahydrocannabinol (THC) and cannabidiol. Some studies have also found that moderate cannabis use may protect against head and neck cancers,<ref></ref>  as well as lung cancer.<ref name="Study finds no marijuana-cancer connection">Template:Cite news</ref> Some studies have shown that cannabidiol may also be useful in treating breast cancer.<ref name="Marijuana compound may stop spread of breast cancer">Template:Cite news</ref>

Cannabis use has been assessed by several studies to be correlated with the development of anxiety, psychosis, and depression.<ref name="pmid=15574485">Template:Cite journal</ref><ref name="pmid12446533">Template:Cite journal</ref> Indeed, a 2007 meta-analysis estimated that cannabis use is statistically associated, in a dose-dependent manner, to an increased risk in the development of psychotic disorders, including schizophrenia.<ref>Template:Cite journal</ref>  However, it is important to note that no causal mechanism has been proven, and the meaning of the correlation and its direction is a subject of debate that has not been resolved in the scientific community. Some studies assess that the causality is more likely to involve a path from cannabis use to psychotic symptoms rather than a path from psychotic symptoms to cannabis use,<ref name="pmid15733249">Template:Cite journal</ref> while others assess the opposite direction of the causality, or hold cannabis to only form parts of a "causal constellation", while not inflicting mental health problems that would not have occurred in the absence of the cannabis use.<ref>Hall, Wayne; Degenhardt, Lousia; Teesson, Maree. "Cannabis Use and Psychotic Disorders: An Update". Office of Public Policy and Ethics, Institute for Molecular Bioscience University of Queensland Australia, and National Drug and Alcohol Research Centre University of New South Wales Australia published in Drug and Alcohol Review (December 2004). Vol 23 Issue 4. pp. 433–443.</ref><ref>Arseneault, Louise; Cannon, Mary; Wiitton, John; Murray, Robin M. "Causal Association Between Cannabis and Psychosis: Examination of the Evidence". Institute of Psychiatry published in British Journal of Psychiatry (2004). #184, pp. 110–117.</ref>

Though cannabis use has at times been associated with stroke, there is no firmly established link, and potential mechanisms are unknown.<ref name="pmid1932970">Template:Cite journal</ref> Similarly, there is no established relationship between cannabis use and heart disease, including exacerbation of cases of existing heart disease.<ref name="pmid18294478">Template:Cite journal</ref> Though some fMRI studies have shown changes in neurological function in long term heavy cannabis users, no long term behavioral effects after abstinence have been linked to these changes.<ref name="pmid17680367">Template:Cite journal</ref>

=== Adulterants ===
Adulterants in cannabis are less common than in other drugs of abuse. Chalk (in the Netherlands) and glass particles (in the UK) have been used at times to make cannabis appear to be higher quality.<ref>Template:Cite web</ref><ref>Template:Cite web</ref><ref>Template:Cite web</ref> Increasing the weight of hashish products in Germany with lead caused lead intoxication in at least 29 users.<ref name="pmid18403778">Template:Cite journal</ref> In the Netherlands two chemical analogs of Sildenafil (Viagra) were found in adulterated marijuana.<ref name="pmid18945564">Template:Cite journal</ref>

== Gateway drug theory ==
<!---***Do Not change the name of the title here, it WILL be reverted.*--->

Some claim that trying cannabis increases the probability that users will eventually use "harder" drugs. This hypothesis has been one of the central pillars of anti-cannabis drug policy in the United States,<ref name="CB">Template:Cite web</ref> though the validity and implications of these hypotheses are highly debated.<ref name="Rand">Template:Cite web</ref> Studies have shown that tobacco smoking is a better predictor of concurrent illicit hard drug use than smoking cannabis.<ref name="pmid8246462">Template:Cite journal</ref>

No widely accepted study has ever demonstrated a cause-and-effect relationship between the use of cannabis and the later use of harder drugs like heroin and cocaine. However, the prevalence of tobacco cigarette advertising and the practice of mixing tobacco and cannabis together in a single large joint, common in Europe, are believed to be a factor in promoting nicotine dependency among young persons investigating cannabis.<ref>Australian Government Department of Health: National Cannabis Strategy Consultation Paper, p. 4. "Cannabis has been described as a 'Trojan Horse' for nicotine addiction, given the usual method of mixing Cannabis with tobacco when preparing marijuana for administration."</ref>

A 2005 comprehensive review of the literature on the cannabis gateway hypothesis found that pre-existing traits may predispose users to addiction in general, the availability of multiple drugs in a given setting confounds predictive patterns in their usage, and drug sub-cultures are more influential than cannabis itself. The study called for further research on "social context, individual characteristics, and drug effects" to discover the actual relationships between cannabis and the use of other drugs.<ref name="pmid16191720">Template:Cite journal</ref>

A new user of cannabis who feels there is a difference between anti-drug information and their own experiences will apply this distrust to public information about other, more powerful drugs. Some studies state that while there is no proof for this gateway hypothesis, young cannabis users should still be considered as a risk group for intervention programs.<ref name="journalwatch">Template:Cite web</ref> Other findings indicate that hard drug users are likely to be "poly-drug" users, and that interventions must address the use of multiple drugs instead of a single hard drug.<ref>Template:Cite web</ref>

Another gateway hypothesis is that while cannabis is not as harmful or addictive as other drugs, a gateway effect may be detected as a result of the "common factors" involved with using any illegal drug. Because of its illegal status, cannabis users are more likely to be in situations which allow them to become acquainted with people who use and sell other illegal drugs.<ref name="morral2002">Template:Cite journal</ref><ref>Template:Cite web</ref> By this argument, some studies have shown that alcohol and tobacco may be regarded as gateway drugs.<ref name="pmid8246462"/> However, a more parsimonious explanation could be that cannabis is simply more readily available (and at an earlier age) than illegal hard drugs, and alcohol/tobacco are in turn easier to obtain earlier than cannabis (though the reverse may be true in some areas), thus leading to the "gateway sequence" in those people who are most likely to experiment with any drug offered.<ref name="Rand"/>

== Legal status ==

<!-- PLEASE, do not add more detail to this section, contributions are more than welcome at Legality of cannabis. THANKS. -->

Main article: Legality of cannabis
Template:See also

Since the beginning of the 20th century, most countries have enacted laws against the cultivation, possession, or transfer of cannabis for recreational use. These laws have impacted adversely on the cannabis plant's cultivation for non-recreational purposes, but there are many regions where, under certain circumstances, handling of cannabis is legal or licensed. Many jurisdictions have lessened the penalties for possession of small quantities of cannabis, so that it is punished by confiscation and sometimes a fine, rather than imprisonment, focusing more on those who traffic the drug on the black market.

In some areas where cannabis use has been historically tolerated, some new restrictions have been put in place, such as the closing of cannabis coffee shops near the borders of the Netherlands,<ref>Many Dutch coffee shops close as liberal policies change, Exaptica, 27/11/2007.</ref> closing of coffee shops near secondary schools in the Netherlands and crackdowns on "Pusher Street" in Christiania, Copenhagen in 2004.<ref>EMCDDA Cannabis reader: Global issues and local experiences, Perspectives on Cannabis controversies, treatment and regulation in Europe, 2008, p. 157.</ref><ref>43 Amsterdam coffee shops to close door, Radio Netherlands, Friday 21 November 2008.</ref>

Some jurisdictions use free voluntary treatment programs and/or mandatory treatment programs for frequent known users. Simple possession can carry long prison terms in some countries, particularly in East Asia, where the sale of cannabis may lead to a sentence of life in prison or even execution.


The price or street value of cannabis varies strongly by region and area. In addition, some dealers may sell potent buds at a higher price.<ref></ref>

In the United States, cannabis is overall the #4 value crop, and is #1 or #2 in many states including California, New York and Florida, averaging $3,000/lb.<ref></ref><ref></ref> It is believed to generate an estimated $36 billion market.<ref>Template:Cite web</ref> Most of the money is spent not on growing and producing but on smuggling the supply to buyers. The United Nations Office on Drugs and Crime claims in its 2008 World Drug Report that typical U.S. retail prices are 10-15 dollars per gram (approximately $290 to $430 per ounce). Street prices in North America are known to range at about $150 to $250 per ounce.<ref>Template:Cite book</ref>

The European Monitoring Centre for Drugs and Drug Addiction reports that typical retail prices in Europe for cannabis varies from 2€ to 14€ per gram, with a majority of European countries reporting prices in the range 4–10€.<ref>Template:Cite book</ref> In the United Kingdom, a cannabis plant has an approximate street value of £300.<ref>£9000</ref>

== Truth serum ==

Cannabis was used as a truth serum by the Office of Strategic Services (OSS), a US government intelligence agency formed during World War II. In the early 1940s, it was the most effective truth drug developed at the OSS labs at St. Elizabeths Hospital; it caused a subject "to be loquacious and free in his impartation of information."<ref name='Whiteout'>Template:Cite book</ref>

In May 1943, Major George Hunter White, head of OSS counter-intelligence operations in the US, arranged a meeting with Augusto Del Gracio, an enforcer for gangster Lucky Luciano. Del Gracio was given cigarettes spiked with THC concentrate from cannabis, and subsequently talked openly about Luciano's heroin operation. On a second occasion the dosage was increased such that Del Gracio passed out for two hours.<ref name='Whiteout'/>

== Breeding and cultivation ==

<!-- PLEASE, do not add more detail to this section, contributions are more than welcome at Cannabis (drug) cultivation. THANKS. -->
File:Cannabis flowering.jpg

Main article: Cannabis cultivation

It is often claimed by growers and breeders of herbal cannabis that advances in breeding and cultivation techniques have increased the potency of cannabis since the late 1960s and early '70s, when THC was first discovered and understood. However, potent seedless marijuana such as "Thai sticks" were already available at that time. Sinsemilla (Spanish for "without seed") is the dried, seedless inflorescences of female cannabis plants. Because THC production drops off once pollination occurs, the male plants (which produce little THC themselves) are eliminated before they shed pollen to prevent pollination. Advanced cultivation techniques such as hydroponics, cloning, high-intensity artificial lighting, and the sea of green method are frequently employed as a response (in part) to prohibition enforcement efforts that make outdoor cultivation more risky. These intensive horticultural techniques have made it possible to grow strains with fewer seeds and higher potency. It is often cited that the average levels of THC in cannabis sold in United States rose dramatically between the 1970s and 2000, but such statements are likely skewed because of undue weight given to much more expensive and potent, but less prevalent samples.<ref>Template:Cite web</ref>


"Skunk" cannabis is a potent strain of cannabis, grown through selective breeding and usually hydroponics, which is a cross-breed of Cannabis sativa and C. indica. Skunk cannabis potency ranges usually from 6% to 15% and rarely as high as 20%. The average THC level in coffee shops in the Netherlands is about 18–19%.<ref>Template:Cite web Ch. 2.3.</ref>

In revisions to cannabis rescheduling in the UK, the government has rescheduled cannabis back from C to B. One of the purported reasons is the appearance of high potency cannabis.<ref>BBC: Cannabis laws to be strengthened. May 2008 20:55 UK.</ref>

A Dutch double-blind, randomized, placebo-controlled, cross-over study examining male volunteers aged 18–45 years with a self-reported history of regular cannabis use concluded that smoking of cannabis with high THC levels (marijuana with 9–23% THC), as currently sold in coffee shops in the Netherlands, may lead to higher THC blood-serum concentrations. This is reflected by an increase of the occurrence of impaired psychomotor skills, particularly among younger or inexperienced cannabis smokers, who do not adapt their smoking style to the higher THC content.<ref>Template:Cite web</ref> High THC concentrations in cannabis was associated with a dose-related increase of physical effects (such as increase of heart rate, and decrease of blood pressure) and psychomotor effects (such as reacting more slowly, being less concentrated, making more mistakes during performance testing, having less motor control, and experiencing drowsiness). It was also observed during the study that the effects from a single joint at times lasted for more than eight hours. Reaction times remained impaired five hours after smoking, when the THC serum concentrations were significantly reduced, but still present. The researchers suggested that THC may accumulate in blood-serum when cannabis is smoked several times per day.

Another study showed that consumption of 15 mg of Δ<sup>9</sup>-THC resulted in no impairment to learning whatsoever occurring over a three-trial selective reminding task after two hours. In several tasks, Δ<sup>9</sup>-THC increased both speed and error rates, reflecting “riskier” speed–accuracy trade-offs.<ref>Template:Cite web</ref>

== See also ==
<div style="-moz-column-count:2; column-count:2; -webkit-column-count:2;">
;Cannabis plant
* Bhang
* Cannabinoids
** Cannabidiol (CBD)
** Cannabinol (CBN)
** Tetrahydrocannabinol (THC)
** Tetrahydrocannabivarin (THCV)
* Cannabis strains
* Hash or hashish
* Hash oil or honey oil
* Hemp oil
* Kief
* Sinsemilla
;Cannabis health
* Medical Cannabis
;Cannabis legality
* 1937 Marihuana Tax Act
* Cannabis political parties
* Global Marijuana March
* International Opium Convention
* Legal and medical status of cannabis
* Legality of cannabis by country
* Marijuana Control, Regulation, and Education Act
* Marijuana Policy Project
* National Organization for the Reform of Marijuana Laws
* List of drugs illegal in the United Kingdom
;Cannabis use demographics
* Adult lifetime cannabis use by country
* Annual cannabis use by country

== Notes ==
<!-- Please do not add any more nicknames, this should give an overview of the most common ones. -->
== References ==

== Further reading ==

* Template:Cite book

== External links ==

Template:Commons category

* Wiktionary Appendix of Cannabis Slang
* Marijuana Policy Project
* National Organization for the Reform of Marijuana Laws
* Comprehensive Cannabis FAQs and Marijuana Information
* The Union: The Business Behind Getting High
* - Cannabis News and Reports
* National Cannabis Prevention and Information Centre
*Tobacco and Marijuana Market Impact Index - National Trends

Template:Drug use
Template:Cannabis resources
Template:California Marijuana

<!-- Currently unused, need to merge back into the article:
== History ==
File:Seed close up.jpg

Cannabis was known as a medicinal and psychoactive compound in some early societies, and has been used continuously in many parts of the world. Other societies have developed a social stigma surrounding the drug.<!-- repression in various Islamic centuries (11th, 13th, and others), early modern (ex-Ottoman) Greece, Egypt under Mehemet Ali (19th century), ...

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