Marijuana (Cannabis)

Effects Classification:
Intoxicant; Stimulant; Psychedelic; Depressant
Common Names: Marijuana, Marihuana, Pot, Weed, Grass, Buds, Green, Reefer, Joint, Blunt, Mary Jane, Ganja, Mota, Hash…
Botanical Classification:
Family: Cannabaceae
Genus: Cannabis
Species: Sativa; Indica; Ruderalis
Description: Cannabis, a fast-growing bushy annual with dense sticky flowers, produces the psychoactive THC. It is the most widely used illegal psychoactive and has a long history of medicinal, recreational, and industrial use. The fibrous stalks of the plant are used to produce clothing and rope.

Basics / General Info


Call it pot, grass, weed, or any one of nearly 200 other names, marijuana is, by far, the world’s most commonly used illicit drug—and far more dangerous than most users realize. So, there is just cause for alarm when adolescent marijuana use increases, as it did in the mid-1990’s, and the age at which youngsters first experiment with pot starts to drops.

Marijuana has been around for a long while. Its source, the hemp plant (cannabis sativa), was being cultivated for psychoactive properties more than 2,000 years ago. Although cannabis contains at least 400 different chemicals, its main mind-altering ingredient is THC (delta-9-tetrahydrocannabinol).The amount of THC in marijuana determines the drug’s strength, and THC levels are affected by a great many factors, including plant type, weather, soil, and time of harvest. Sophisticated cannabis cultivation of today produces high levels of THC and marijuana that is far more potent than pot of the past. THC content of marijuana, which averaged less than 1 percent in 1974, rose to an average 4 percent by 1994.

For the highly popular form of marijuana called Sinsemilla (from the Spanish “without seeds”), made from just the buds and flowering tops of female plants, THC content averages 7.5 percent and ranges as high as 24 percent. As for hashish, a resin made from flowers of the female plant, THC levels may be five to ten times higher than crude marijuana’s.

How is it Used?

Marijuana and other cannabis products are usually smoked, sometimes in a pipe or water pipe, but most often in loosely rolled cigarettes known as “joints.” Some users will slice open and hollow out cigars, replacing the tobacco with marijuana, to make what are called “blunts.” Joints and blunts may be laced with other substances, including crack cocaine and the potent hallucinogen phencyclidine (PCP), substantially altering effects of the drug.

Smoking, however, is not the sole route of administration. Marijuana can be brewed into tea or mixed in baked products (cookies or brownies).

Teens and Marijuana

Although dangers exist for marijuana users of all ages, risk is greatest for the young. For them, the impact of marijuana on learning is critical, and pot often proves pivotal in the failure to master vital interpersonal coping skills or make appropriate life-style choices. Thus, marijuana can inhibit maturity.

Another concern is marijuana’s role as a “gateway drug,” which makes subsequent use of more potent and disabling substances more likely. The Center on Addiction and Substance Abuse at Columbia University found adolescents who smoke pot 85 times more likely to use cocaine than their non–pot smoking peers. And 60 percent of youngsters who use marijuana before they turn 15 later go on to use cocaine.

But many teens encounter serious trouble well short of the “gateway.” Marijuana is, by itself, a high-risk substance for adolescents. More than adults, they are likely to be victims of automobile accidents caused by marijuana’s impact on judgment and perception. Casual sex, prompted by compromised judgment or marijuana’s disinhibiting effects, leaves them vulnerable not only to unwanted pregnancy but also to sexually transmitted diseases (STDs).



A mild hallucinogen, marijuana has some of alcohol’s depressant and disinhibiting properties. User reaction, however, is heavily influenced by expectations and past experience, and many first-time users feel nothing at all.

Effects of smoking are generally felt within a few minutes and peak in 10 to 30 minutes. They include dry mouth and throat, increased heart rate, impaired coordination and balance, delayed reaction time, and diminished short-term memory. Moderate doses tend to induce a sense of well-being and a dreamy state of relaxation that encourages fantasies, renders some users highly suggestible, and distorts perception (making it dangerous to operate machinery, drive a car or boat, or ride a bicycle). Stronger doses prompt more intense and often disturbing reactions including paranoia and hallucinations.

Most of marijuana’s short-term effects wear off within two or three hours. The drug itself, however, tends to linger on. THC is a fat-soluble substance and will accumulate in fatty tissues in the liver, lungs, testes, and other organs. Two days after smoking marijuana, one-quarter of the THC content may still be retained. It will show up in urine tests three days after use, and traces may be picked up by sensitive blood tests two to four weeks later.



Marijuana Dangers

Impaired perception
Diminished short-term memory
Loss of concentration and coordination
Impaired judgement
Increased risk of accidents
Loss of motivation
Diminished inhibitions
Increased heart rate
Anxiety, panic attacks, and paranoia
Damage to the respiratory, reproductive, and immune systems
Increased risk of cancer
Psychological dependency

Marijuana use reduces learning ability. Research has been piling up of late demonstrating clearly that marijuana limits the capacity to absorb and retain information. A 1995 study of college students discovered that the inability of heavy marijuana users to focus, sustain attention, and organize data persists for as long as 24 hours after their last use of the drug. Earlier research, comparing cognitive abilities of adult marijuana users with non-using adults, found that users fall short on memory as well as math and verbal skills. Although it has yet to be proven conclusively that heavy marijuana use can cause irreversible loss of intellectual capacity, animal studies have shown marijuana-induced structural damage to portions of the brain essential to memory and learning.

The Impact on the Body

Chronic marijuana smokers are prey to chest colds, bronchitis, emphysema, and bronchial asthma. Persistent use will damage lungs and airways and raise the risk of cancer. There is just as much exposure to cancer-causing chemicals from smoking one marijuana joint as smoking five tobacco cigarettes. And there is evidence that marijuana may limit the ability of the immune system to fight infection and disease.

Marijuana also affects hormones. Regular use can delay the onset of puberty in young men and reduce sperm production. For women, regular use may disrupt normal monthly menstrual cycles and inhibit ovulation. When pregnant women use marijuana, they run the risk of having smaller babies with lower birth weights, who are more likely than other babies to develop health problems. Some studies have also found indications of developmental delays in children exposed to marijuana before birth.


The origin of the word marijuana is not known but it appears to be the Spanish name for Maria and Juana (Mary and Jane). The drug slang for marijuana includes such names as Mary Jane, pot, grass, tea, reefer (as a cigarette), and weed. In India it is called ghanja, dagga in South Africa, and Kef in Morocco. The potency of the psychoactive cannabinoids found in a marijuana plant varies depending on the locale from which the plant was derived and its genetic makeup.

Reference to the hemp plant (cannabis) appears as early as 2700 B.C. in a Chinese manuscript. European explorers arriving to the New World first observed the plant in 1545. It was considered to be such a useful crop that early Jamestown settlers in 1607 began its cultivation and later in Virginia farmers were fined for not growing hemp; in 1617, it was introduced into England. From the seventeenth to the mid-twentieth century marijuana was considered as a household drug useful for treating such maladies as headaches, menstrual cramps, and toothaches. From 1913-38 a stronger variety of the marijuana plant was cultivated by American drug companies for use in their drug products. It was called Cannabis americana.

Prior to 1910, the growth and trade of marijuana (and hashish—a resinous substance produced by the flowering parts of the plant) was fairly limited. However, following the conclusion of the Mexican Revolution, trafficking of the drug opened up, making growth and transport of the drug easier and more profitable. The business expanded to reach the ports of New Orleans where it was sold on the black market, alongside other strains of the plant, to sailors passing through, as well as local residents. It wasn’t long before the trend of marijuana use began to overshadow the historic applications of cannabis as a medicine.

The drug soon became popular (especially its stronger derivitives—hashish, charas, ghanja, and bhang) among musicians who maintained that smoking marijuana gave them the inspiration they needed to play their music. These musicians glamorized the use of marijuana. Some claimed it gave them contemplative vision and a feeling of overwhelming freedom and verve; others not only used the drug themselves, but sold it to a variety of customers. As the entertainers went on the road, so did their drugs. Eventually, use of marajuana, alcohol, and other mind-altering drugs spread and soon became prevalent in major cities worldwide, such as Chicago, New York, London, and Paris.

Many of the musicians and entertainers of the Jazz Age who used drugs and alcohol relied heavily on gangland kings for their “gigs” (jobs). Frequently, these gangsters were able to provide (for a fee) a variety of drugs and bootleg alcohol for the performers and their staffs.

In the 1920s, as a result of the amendment prohibiting the use of alcoholic beverages (Prohibition), marijuana use as a psychoactive drug began to grow. Even after the repeal of Prohibition in 1933, marijuana was widely used as were morphine, heroin, and cocaine. In 1937, 46 states banned the use of marijuana along with other narcotic drugs. The popular perception, however, was that marijuana was not as addictive as narcotic. It is classified today as a drug that alters mood, perception, and image, rather than as a narcotic drug.

By the 1960s it was widely used by the young from all social classes. It is estimated that by the 1970s as many as 43 million Americans had used marijuana. The presence of more potent strains of marijuana has widened the debate between the drug enforcement authorities and the advocates of decriminalizing marijuana use because it is, they believe, not in the same class as the more addictive drugs. Others see marijuana as a “gateway” drug to the harder drugs and therefore believe rigid laws against its use and distribution should remain in effect.

Marijuana affects both the cardiovascular and central nervous systems. At low doses there tends to be a sense of well-being, drowsiness, and relaxation. As the dose increases, other effects take place such as an altered sense of time and sensory awareness, difficulty in balancing and remembering from one moment to another (short-term memory). Conversation and thoughts become incomplete, and exaggerated laughter may take place with increased doses. At higher doses, severe psychological disturbances can take place such as paranoia, hallucinations, panic attacks, and the acting out of delusions.

The cardiovascular system is affected by an increased heart rate and dilation of eye blood vessels. Difficulty in coordinating body movements and pains in the chest may be other effects of the drug. Less is known about marijuana’s effects on the lungs than cigarette smoking, but the evidence points to long-term damage similar to the effects of tobacco smoking.

The FDA in 1985 gave approval for the use of two psychoactive chemicals from marijuana to prevent nausea and vomiting after chemotherapy in cancer treatment. Other proposed medical uses of marijuana are for the treatment of glaucoma, as a bronchodilator, as an antidepressant, and for several other types of medical treatment drugs.



Marijuana as Medicine

Although U.S. law classifies marijuana as a Schedule I controlled substance (which means it has no acceptable medical use), a number of patients claim that smoking pot has helped them deal with pain or relieved the symptoms of glaucoma, the loss of appetite that accompanies AIDS, or nausea caused by cancer chemotherapy. There is, however, no solid evidence that smoking marijuana creates any greater benefits than approved medications (including oral THC) now used to treat these patients, relieve their suffering, or mitigate the side effects of their treatment. Anecdotal assertions of beneficial effects have yet to be confirmed by controlled scientific research.

Marijuana-like substance in brain could help treat Parkinson’s, researchers say, Feb 2007,
Marijuana Production in the United States (2006) – (PDF), Dec 2006
Study turns pot wisdom on its head – Globe and Mail, Oct 14 2005
Marijuana may block Alzheimer’s – BBC, Feb 22 2005
Cannabis chemical pregnancy link – BBC, Sep 19 2004