Marijuana Cannabis Effects
What is Marijuana?
Some 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).
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.
The Impact on the Mind
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.
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.
Wikipedia, The Free Encyclopedia. 2006. 12 Dec. 2007 <http://en.wikipedia.org/wiki/Marijuana>.
Wikipedia, The Free Encyclopedia. 2006. 12 Dec. 2007 <http://en.wikipedia.org/wiki/Drugs>.
Holt, Rinehart. "53." Modern Biology. Rinehart and Hart, 2002. 1064-1079.