Cannabis (drug)

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This article is about cannabis used as a drug. For other uses, see cannabis.
Cannabis leaves are less potent than the flowers.
Cannabis 'bud', 'manicured' female flowers, are slowly and carefully dried to produce a well-cured product and conserve taste and potency.
File:61bud1.jpg
Growing cannabis flowers must be harvested at the appropriate point of maturation for maximum potency and flavor.

The Cannabis sativa plant can be dried or otherwise processed to yield products containing large concentrations of compounds that have medicinal and psychoactive effects when ingested, usually by smoking or eating. Cannabis has been used for medical and psychoactive effects for thousands of years. In the early 20th century, there was a sudden upswing in the use of cannabis as a psychoactive substance, mostly for recreational purposes but to some extent for religious purposes. Due to negative media attention regarding its psychoactive effects, as well as heavy lobbying from pharmaceutical companies, the possession, use, or sale of psychoactive cannabis products became illegal in most parts of the world during the early twentieth century, and remains that way today. For the physiology and science of the plant see Cannabis sativa.

History of cannabis usage

Cannabis has been known as a medicinal and psychoactive compound since early times, and was used in this fashion without stigma until its criminalization in the early 20th century.

Ancient history

Cannabis was well known to the Scythians, as well as by the Thracians/Dacians, whose shamans (the kapnobatai - "those who walk on smoke/clouds") used to burn cannabis flowers in order to induce trances. The cult of Dionysus, which is believed to have been originated in Thrace, has also been linked to the effects of cannabis smoke. The most famous users of cannabis though were the ancient Hindus. According to legend, Shiva, the destructive aspect of the Hindu trinity, told his disciples to use the hemp plant in all ways possible. Cannabis is also thought by some to be the ancient drug soma, mentioned in the Vedas as a sacred intoxicating hallucinogen, although a number of advocates for different psychoactive substances such as Amanita muscaria and Salvia Divinorum make this claim as well.

Recent history

Under the name cannabis 19th-century medical practitioners helped to introduce the herb's drug potential (usually as a tincture) to modern English-speaking consciousness. It was famously used to treat Queen Victoria's menstrual pains, and was available from shops in the US. By the end of the 19th century its medicinal use began to fall as other drugs such as aspirin took over.

The name marijuana is Mexican or Latin American in origin and associated almost exclusively with the herb’s drug potential. That marijuana is now well known in English as a name for drug material is due largely to the efforts of US drug prohibitionists during the 1920s and 30s, who used a hispanic name for cannabis in order to turn the populace against the idea that it should be legal.

Although cannabis has been used for its psychoactive effects since ancient times, it first became well known in the United States during the jazz music scene of the late 1920s and 30s. Louis Armstrong became one of its most prominent and life-long devotees. Cannabis use was also a prominent part of 1960s counterculture.

Prohibition and criminalization in the US

Until 1937, consumption and sale of cannabis was legal in most American states. In some areas it could be openly purchased in bulk from grocers or in cigarette form at newsstands, though an increasing number of states had begun to outlaw it. In that year, federal law made possession or transfer of cannabis (without the purchase of a by-then-incriminating tax stamp) illegal throughout the United States. This was contrary to the advice of the American Medical Association at the time. Legal opinions of time held that the federal government could not outlaw it entirely. The tax was $100 per pound of hemp, even for clothes or rope. The expense, extremely high for that time, was such that people stopped buying and making it.

The decision of the U.S. Congress was based in part on testimony derived from articles in the newspapers owned by William Randolph Hearst, who was heavily interested in DuPont Inc. Some analysts theorize DuPont wanted to boost declining post-war textile sales, and wished to eliminate hemp fiber as competition. Many argue that this seems unlikely given DuPont's lack of concern with the legal status of cotton, wool, and linen; although it should be noted that hemp's textile potential had not yet been largely exploited, while textile factories already had made large investments in equipment to handle cotton, wool, and linen. Others argue that Dupont wanted to eliminate cannabis because its high natural cellulose content made it a viable alternative to the company's developing innovation: modern plastic. Still, others could argue that hemp could never truly compete with the high strength and elasticity of synthetics, such as nylon. Furthermore, hemp would have been an easy target due to its intoxicating effect, while no rational justification could have been made for outlawing cotton, wool, or linen.

File:Marahuana warning.png
U.S. Federal Bureau of Narcotics poster used in the late 1930s and 1940s.

During this period, Henry (Harry) Anslinger alleged that the drug could provoke criminal behavior in previously solid citizens. Anslinger also popularized the word marihuana for the plant, using a Mexican derived word (believed to be derived from a Brazilian Portuguese term for inebriation) in order to associate the plant with increasing numbers of Mexican immigrants, creating a negative stereotype which persists to this day.

The 1937 federal marijuana tax act was struck down by the Supreme Court in 1969. In a case brought by Timothy Leary, the Court held that the law's requirement that a would-be possessor of marijuana register with the local bureau of the IRS, thereby placing his name and address on a file available to local law enforcment, violated the Fifth Amendment privilege against self-incrimination, given the fact that at the time all 50 states had state laws on the books outlawing marijuana outright. In 1970, the Controlled Substances Act made possession of marijuana illegal again on a federal level, without the constitutional issues that scuttled the 1937 act. Several petitions for cannabis rescheduling in the United States have been filed, since the Act permits legalization of marijuana through the executive branch.

Immediate effects of human consumption

The nature and intensity of the immediate effects of cannabis consumption vary according to the dose, the species or hybridization of the source plant, the method of consumption, the user's mental and physical characteristics (such as possible tolerance), and the environment of consumption. Effects of cannabis consumption may be loosely classified as cognitive and physical. Anecdotal evidence suggests that the Cannabis sativa species tends to produce more of the cognitive or perceptual effects, while Cannabis indica tends to produce more of the physical effects.

Cognitive, behavioral, or perceptual

Cannabis has a broad spectrum of cognitive, behavioral, or perceptual effects. Some of these are the intended effect desired by users, some may be considered desirable depending on the situation, and others are generally considered undesirable. Users of cannabis report that these kinds of effects are more often produced by the sativa species of Cannabis.

Generally desirable effects

Situationally desirable effects

  • Increased awareness of sensation
  • Initial wakefulness followed by drowsiness and lassitude
  • Disruption of linear memory
  • Increased awareness of patterns and color
  • Increased or decreased verbalization
  • Loss or gain of inhibitions

Generally undesirable effects

Physical or sensory

Cannabis also has effects that are predominantly physical or sensory. It is widely believed that the indica species of Cannabis is more likely to produce effects like these.

Therapeutic effects

  • Pain relief (especially headaches and cramps).
  • Increased appetite, food subjectively tastes better.
  • Reduced nausea, (especially from chemotherapy), though may cause or exacerbate nausea, due to feelings of anxiety that may arise in some users.
  • Dilation of alveoli (air sacs) in lungs, resulting in deeper respiration.
  • Dilation of blood vessels (vasodilation), resulting in:
    • Increased blood flow and heart rate
    • Reddening of the conjunctivae (red eye)
  • Lower intra-ocular pressure (beneficial to Glaucoma patients).
  • Lower blood pressure while standing. Higher blood pressure while sitting.
  • Increased metabolism of glucose, reducing blood sugar levels.

Other effects

  • Dry mouth

Active ingredients, metabolism, and method of activity

Of the approximately 400 different chemicals found in Cannabis, the main active ingredient is tetrahydrocannabinol (delta-9-tetrahydrocannabinol, THC). THC can degrade to CBL & CBN (other cannabinoids), which can make one feel sleepy and disoriented. Different marijuana products have different ratios of these and other cannabinoids. Depending on the ratio, the quality of the "high" will vary.

THC has an effect on the modulation of the immune system which may have an effect on malignant cells, but there is insufficient scientific study to determine whether this might promote or limit cancer. Cannabinoid receptors are also present in the human reproductive system, but there is insufficient scientific study to conclusively determine the effects of cannabis on reproduction. Mild allergies to cannabis may be possible in some members of the population.

Lethal dose

No fatal overdose due to cannabis use has ever been recorded in humans. According to the Merck Index, 12th edition, the LD50, the lethal dose for 50% of tested rats, was 42 milligrams per kilogram of body weight with forced inhalation, equivalent for a 165 lb. male to all of the THC in 21 one-gram cigarettes of maximum-potency (15% THC) cannabis buds, assuming no THC was lost through burning or inhalation. For oral consumption, the LD50 for rats was 1270 mg/kg and 730 mg/kg for males and females, respectively, equivalent to the THC in about a pound of 15% THC cannabis. It would be impossible for THC in blood plasma to reach such a level in human cannabis smokers. Only with intravenous administration, a method rarely used by humans, may such a level be possible. Also, some evidence suggests that toxic levels may be higher for humans than for rats.

Long-term effects of human consumption

Main article: Health issues and the effects of cannabis

There is little conclusive scientific evidence about the long-term effects of human cannabis consumption. The findings of earlier studies purporting to demonstrate the effects of the drug are unreliable, as the studies were deeply flawed, with strong bias and poor methodology. The most significant confounding factor is the use of other drugs, including alcohol and tobacco, by test subjects in conjunction with cannabis. When subjects using only cannabis were combined in the same sample with subjects using other drugs as well, researchers could not reach a conclusion as to whether their findings were caused by cannabis, other drugs or the interaction between them.

Tolerance, withdrawal and dreams

Although use may become habitual, the extent of physical dependence to cannabis is unknown. (DEA, 2004) Yet, many animal and human studies conducted since the 1970s have revealed a cannabis withdrawal syndrome in some people after abstinence from heavy use which is usually characterized by several days of anxiousness, sleeplessness or more vivid, memorable dreams (REM rebound), irritability, and diminished appetite after cessation of use. However, because cannabis is a peculiar psychedelic that is unlike typical depressant or stimulant drugs, these persistent effects are unlike those normally associated with physical dependence. THC has a very long half-life, working its way out of the body slowly over many days, which reduces its potential to cause severe physical withdrawal symptoms. This is disputed, however; while some substances resulting from THC decomposition indeed stay in the body for a long time, these have not proven to have any physical or mental effects in themselves, and intact THC molecules do not last very long after ingestion.

Long-term effects on the mind and brain

In some people, cannabis use appears to cause significant medium-term decreases in cognitive performance, but performance on general intelligence and cognitive tests returns to "normal" in those people affected in this way within weeks of abstinence depending on the level of use. However, subtle impairment of complex cognitive function may persist even after long periods of abstinence in some of the users who suffered from decreased cognitive performance in the first place.

There is a growing body of medical evidence to show a link in some people between cannabis use and psychosis, schizophrenia, and clinical depression. Some believe that cannabis may trigger latent conditions or be part of a complex coordination of causes, referred to as the diathesis-stress model in psychology. On the other hand, many people with pronounced psychological disorders, especially schizophrenia and depression, often self-medicate their illness with cannabis in place of potent main-stream drugs like antipsychotics, due to cannabis's relatively low side effects and calming physiological effects that alleviate symptoms. Though cannabis has been used for thousands of years, and has been increasingly popular in the west since the sixties it is only since the nineties that the link between cannabis and psychosis has been identified.

One concern with research that identified correlation between cannabis use and psychotic illness has been that, where cannabis is thought to be helpful in treating medical conditions, a correlation may easily be drawn which does not imply causality attributable to cannabis. Recent research has addressed this concern by studying large groups free of mental illness, to examine the proportion of individuals that already use cannabis who go on to develop mental illnesses[1].

Further evidence for causality was provided by a 2005 study[2] showing the existence of a genetic predisposition to cannabis related symptoms of psychosis, showing significant correlation between genetic factors, cannabis use and symptoms of psychotic illness. The study demonstrates that adolescent cannabis usage is a predictor for symptoms of adult psychosis in the estimated 25% of the population with these genotypes[3]. The study is adjusted for prior evidence of mental illness, and for several other alternative explanations. This argument is still hotly disputed[4] [5], and research is ongoing.

Some claim that extended use of cannabis may help a human reach a higher level of mental consciousness and clarity, expanding the mind and helping individuals become more aware, insightful and intelligent.

These claims may seem to be contradictory while indicating differing views of a common effect.

Long-term physical effects of smoking

The combustion of any organic material creates irritants and carcinogens, and cannabis is no different. The long-term effects of smoking any substance depends on frequency of use, duration of inhalation, and composition of the smoke. This leads many to assume that the effects of cannabis can be directly compared to other well-known smoking materials such as tobacco. However, direct comparisons of the two are probably invalid because the chemical composition and methods of usage are not the same. Studies on the subject are inconclusive and have not isolated all the possible factors exacerbating or ameliorating the effects of cannabis user. Here are some of these factors:

Possibly exacerbating factors:

  • Studies have pointed out that cannabis produces more tar and burns at a higher temperature than tobacco.
  • Some cannabis smokers inhale the smoke more deeply and hold it in their lungs for a longer period of time.

Possibly ameliorating factors

  • Generally, even a chronic cannabis user does not inhale a daily volume of smoke equal to that of a tobacco smoker.
  • Industrialized cultivation and preparation of tobacco introduces a variety of toxic and carcinogenic additives and congeners such as nitrosamines, arsenic, radium-226, and polonium-210. In home-grown cultivation, these contaminants are less likely to be introduced.
  • There is evidence to suggest that cannabinoids present in cannabis may actually serve to protect against cancer. [6]

While some studies have claimed a positive correlation between cannabis use and lung cancer, this might primarily indicate only that cannabis use may correlate with tobacco use, and more objective scientific attention is needed to separate these and other factors in order to better understand the potential long-term physiological effects of cannabis use itself. Updated reports seem to suggest that when the data is properly analyzed, the correlation may in fact be negative.[7]

Medical use

Main article: Medical marijuana

Medically, cannabis is most often used as an appetite stimulant and pain reliever for certain terminal illnesses such as cancer and AIDS. It is also used to relieve glaucoma and certain neurological illnesses such as epilepsy, migraine and bipolar disorder. The medical use of cannabis is politically controversial, but it is sometimes recommended informally by physicians. A synthetic version of the major active chemical in cannabis, THC, is readily available in the form of a pill as the prescription drug Marinol. THC has also been found to reduce arterial blockages.[8] A sublingual spray derived from an extract of cannabis has also been approved for treatment of multiple sclerosis in Canada as the prescription drug Sativex.

See section History for information on historic and other medical use.

Spiritual use

Main article: Cannabis (spiritual use)

Cannabis has a long history of spiritual use, especially in India, where it has been used by wandering spiritual sadhus for centuries. The most famous religious group to use cannabis in a spiritual context are the Rastafari movement, though they are by no means the only group. Some historians and etymologists have claimed that cannabis was used by ancient Jews, early Christians and Muslims of the Sufi order.

Many individuals also consider their use of cannabis to be spiritual regardless of organized religion.

Preparations for human consumption

File:Weed full.schmiddy.jpeg
Roughly 3.5 grams (1/8 ounce) of cannabis buds in a plastic bag.
A cigarette rolling machine (A), a cannabis spliff (B), a small amount of crushed cannabis (C), and a book of cigarette rolling papers (D).
Glass smoking pipe.

Cannabis is prepared for human consumption in several forms:

  • Marijuana or buds, the resin gland-rich flowering tops of female plants.
    • Sinsemilla or sensemillia, flowering tops which are free of seeds as a result of being grown in a pollen-free environment. Since no plant energy can go into seed formation, this version is higher in psychoactive components.
  • kief or kif, a powder containing the resin glands (glandular trichomes, often incorrectly called "crystals" or "pollen"). It is produced by sifting marijuana and leaves.
  • Hashish, a concentrated resin made from pressing kif into blocks.
  • Charas, produced by hand-rubbing the resin from the resin gland-rich parts of the plant. Often thin dark rectangular pieces.
  • Bhang, prepared by the wet grinding of the leaves of the plant and used as a drink.
  • Hash oil, resulting from extraction or distillation of THC-rich parts of the plant.
  • Minimally potent leaves and detritus, called shake, bush or leaf.

There are also three different species of Cannabis. These include Cannabis sativa, Cannabis indica, and Cannabis ruderalis, the latter containing somewhat less THC. They differ in their appearance and the highs they produce.

Smoking

The most common method of cannabis consumption is by smoking a hit through one of several classes of devices:

  1. By rolling it up, either manually or with a rolling machine, into a cigarette, often called a spliff or joint, with thin rolling papers, or into a cigar, often called a blunt, with wrapper obtained by removing the tobacco from the inside of a standard cigar. In such preparation, tobacco or other smokable material are sometimes combined into a single roll.
  2. By using a smoking pipe, often called a bowl, usually made of blown glass, wood, or sometimes metal. Blown-glass pipes are usually intricately and colorfully designed, with colors becoming more vivid after repeated use. Such pipes usually have a rush or carb or shotgun hole which is covered by a finger for suction when beginning smoking, which is released to finish inhalation, thus clearing the pipe of smoke without advancing the burning any further. Tobacco pipes, pipes home-made by the user, and others, are also sometimes used. Some users prefer a vertically held ceramic or glass pipe, known as a chillum, coming from India.
  3. In a water-pipe, or bong, by which the smoke is filtered through water into a large chamber. It should be noted that smoking from a bong loaded with cold water or ice will greatly cool the smoke and reduce heat-related damage. Bong use is common and enables smoking techniques that are not possible with a simple smoking pipe. Other designs include the waterfall bong and bucket bong. The term gravity bong has different meaning in different cultures but usually refers to either of these two latter devices.
  4. A further method, commonly referred to as spotting or hot knives, is when two knives are heated (usually on a stove-top element) until red-hot. A small amount of resin, or marijuana (oil or bud), known as a spot is then pressed between the knives and the resulting smoke inhaled through a funnel, often made from a bottomless soft-drink bottle. This method is often used when no other materials for smoking are at hand, and is also thought to be more efficient, as there is no idle burning between inhalations. This method is more efficient because THC is destroyed at high temperatures, rather than released from the plant material. Hot knives, assuming they're not too hot, release more THC than they destroy, heightening the high. Done properly, this method can replicate the Vaporisation method mentioned below.

Oral consumption

Cannabis may be orally consumed by blending it with alcohol or fats. With this method, some claim that more cannabis must be used. The effects of the drug take longer to begin, but last longer and may be more physical rather than mental. It is thought that the active component of cannabis, delta- 9 THC, is converted to the more psychoactive delta-11 THC in the liver. It takes some experience for one to regulate the dose. Common preparations involve blending with butter that is used in preparing brownies, fudge or cookies. Infusion in drinks containing milk and flavoring herbs is also possible, and more common in India.

As with other drugs that are taken orally, it is sometimes customary to fast before taking the drug to increase the effect (possibly because an empty stomach will absorb the drug faster so it 'hits' you more strongly). Still, it usually takes more than an hour for the effects to set in, as opposed to smoking, where it takes a few minutes.

Preparing cannabis for oral consumption must be done with fats or alcohol. Contrary to popular belief, cannabis tea does not contain significant amounts of THC, because THC, along with the other cannabinoids, is highly insoluble in water, but readily dissolves into fats and alcohol. The tea is, however, reputed to be a tasty and relaxing drink.

The seeds of the plant, high in protein and fatty acids, can also be roasted and eaten. They contain little THC.

See Cooking with cannabis external links below.

Vaporization

Usually with a vaporizer, cannabis can be heated to a temperature of about 365 °F at which the active ingredients are released into gaseous form with little or no burning of the plant material. With this method, the user does not inhale as many toxic chemicals that are byproducts of combustion and so may be less harmful. It is worth noting that the effects of combustion break down many of the cannabinoids present in cannabis to varying degrees when smoked. By contrast, vaporization may preserve some of these cannabinoids, although the concentrations of the various cannabinoids may be disparate to those in smoked cannabis. As a result, some users claim to experience subtly different effects when using cannabis in this way. In addition, users note an improved ability to distinguish subtle characteristics of flavor and aroma, in absence of lighter gas fumes or burnt matter.

Legality

Main article: Legal issues of cannabis

Since the twentieth century, most countries have laws against the cultivation, use, possession, or transfer of cannabis (and, naturally, these laws impact adversely on the herb's cultivation for non-drug purposes) but there are many regions where certain circumstances of cannabis handling are legal or licensed and others where laws against its use, possession, or sale are not enforced. Many jurisdictions have also decriminalized possession of small quantities of cannabis, so that it is punished by confiscation and/or a fine, rather than imprisonment. By effectively removing the user from the criminal justice system, decriminalization focuses more on those who traffic and sell the drug on the black market. Increasingly, many jurisdictions also permit cannabis use for medicinal purposes.

US state-by-state laws regarding penalties for possession and sale of cannabis can be found at:

http://www.norml.org/index.cfm?Group_ID=4516

Related articles

External links

Wikimedia Commons has media related to Cannabis sativa.

Information

History

Advocacy

Growing and consuming

Main article: Cannabis cultivation
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