What is Cannabis?
Cannabis is the most commonly abused illicit drug in South Africa. It is a dry, shredded green and brown mix of flowers, stems, seeds, and leaves derived from the hemp plant Cannabis sativa. The main active chemical in cannabis is delta-9-tetrahydrocannabinol; THC for short.
How is Cannabis abused?
Cannabis is usually smoked as a cigarette (joint) or in a pipe. It is also smoked in blunts, which are cigars that have been emptied of tobacco and refilled with cannabis. Since the blunt retains the tobacco leaf used to wrap the cigar, this mode of delivery combines cannabis's active ingredients with nicotine and other harmful chemicals. Cannabis can also be mixed in food or brewed as a tea. As a more concentrated, resinous form it is called hashish, and as a sticky black liquid, hash oil.* Cannabis smoke has a pungent and distinctive, usually sweet-and-sour odour.
Long-term cannabis abuse can lead to addiction; that is, compulsive drug seeking and abuse despite its known harmful effects upon social functioning in the context of family, school, work, and recreational activities. Long-term cannabis abusers trying to quit report irritability, sleeplessness, decreased appetite, anxiety, and drug craving, all of which make it difficult to quit. These withdrawal symptoms begin within about 1 day following abstinence, peak at 2–3 days, and subside within 1 or 2 weeks following drug cessation.
How does Cannabis affect the brain?
Scientists have learned a great deal about how THC acts in the brain to produce its many effects. When someone smokes cannabis, THC rapidly passes from the lungs into the bloodstream, which carries the chemical to the brain and other organs throughout the body. THC acts upon specific sites in the brain, called cannabinoid receptors, kicking off a series of cellular reactions that ultimately lead to the “high” that users experience when they smoke cannabis. Some brain areas have many cannabinoid receptors; others have few or none. The highest density of cannabinoid receptors are found in parts of the brain that influence pleasure, memory, thoughts, concentration, sensory and time perception, and coordinated movement. Not surprisingly, Cannabis intoxication can cause distorted perceptions, impaired coordination, difficulty in thinking and problem solving, and problems with learning and memory. Research has shown that Cannabis’s adverse impact on learning and memory can last for days or weeks after the acute effects of the drug wear off. As a result, someone who smokes cannabis every day may be functioning at a suboptimal intellectual level all of the time. Research on the long-term effects of cannabis abuse indicates some changes in the brain similar to those seen after long-term abuse of other major drugs. For example, cannabinoid withdrawal in chronically exposed animals leads to an increase in the activation of the stress-response system3 and changes in the activity of nerve cells containing dopamine. Dopamine neurons are involved in the regulation of motivation and reward, and are directly or indirectly affected by all drugs of abuse.
Cannabis and mental health
A number of studies have shown an association between chronic cannabis use and increased rates of anxiety, depression, suicidal ideation, and schizophrenia. Some of these studies have shown age at first use to be a factor, where early use is a marker of vulnerability to later problems. However, at this time, it not clear whether cannabis use causes mental problems, exacerbates them, or is used in attempt to self-medicate symptoms already in existence. Chronic cannabis use, especially in a very young person, may also be a marker of risk for mental illnesses, including addiction, stemming from genetic or environmental vulnerabilities, such as early exposure to stress or violence. At the present time, the strongest evidence links cannabis use and schizophrenia and/or related disorders. High doses of cannabis can produce an acute psychotic reaction, and research suggests that in vulnerable individuals, cannabis use may be a factor that increases risk for the disease.
What other adverse effect does Cannibas have on health?
Effects on the heart
One study found that an abuser’s risk of heart attack more than quadruples in the first hour after smoking cannabis.7 The researchers suggest that such an outcome might occur from cannabis’s effects on blood pressure and heart rate (it increases both) and reduced oxygen-carrying capacity of blood.
Effects on the lungs
Numerous studies have shown cannabis smoke to contain carcinogens and to be an irritant to the lungs. In fact, cannabis smoke contains 50 to 70 percent more carcinogenic hydrocarbons than tobacco smoke. Cannabis users usually inhale more deeply and hold their breath longer than tobacco smokers do, which further increases the lungs’ exposure to carcinogenic smoke. Cannabis smokers show dysregular growth of epithelial cells in their lung tissue, which could lead to cancer; however, a recent case-controlled study found no positive associations between cannabis use and lung, upper respiratory, or upper digestive tract cancers. Thus, the link between cannabis smoking and these cancers remains unsubstantiated at this time. Nonetheless, cannabis smokers can have many of the same respiratory problems as tobacco smokers, such as daily cough and phlegm production, more frequent acute chest illness, a heightened risk of lung infections, and a greater tendency toward obstructed airways. A study of 450 individuals found that people who smoke cannabis frequently but do not smoke tobacco have more health problems and miss more days of work than non-smokers. Many of the extra sick days among the cannabis smokers in the study were for respiratory illnesses.
Effects on daily life
Research clearly demonstrates that cannabis has the potential to cause problems in daily life or make a person’s existing problems worse. In one study, heavy cannabis abusers reported that the drug impaired several important measures of life achievement including physical and mental health, cognitive abilities, social life, and career status. Several studies associate workers’ cannabis smoking with increased absences, tardiness, accidents, workers’ compensation claims, and job turnover.
Treatment for Marijuana
The question is what can be done to help people become and remain abstinent. For those who cannot remain abstinent, an initial goal is measurable improvement. The first step for clinicians is to help the patient become motivated to change his relationship to drugs. Treatment programs focus on counselling and group support systems. Another model for treatment involves one-on-one intervention, followed by an assessment session that provides an overview to the patient, an in-depth discussion about the patient’s use of marijuana and reasons for favoring or opposing quitting and answers to questions the client has about quitting or modifying use.
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