Marijuana, also known as cannabis, is one of the most frequently used recreational drugs in the United States and many European countries. Approximately 26 million (9%) individuals over the age of 12 years were reported to have used marijuana in the previous month, according to the 2017 National Survey on Drug Use and Health (NSDUH) report.
Although marijuana has been legalized in many states for both recreational and medicinal use, long-term marijuana use can cause dependence and is associated with adverse social, psychological and physical effects.
What Is Marijuana?
Marijuana is a psychoactive (or mind-altering) drug obtained from the dried leaves, seeds, stems and flowers of the hemp plants Cannabis sativa or Cannabis indica. Marijuana is also referred to as cannabis or weed. Marijuana contains more than 60 compounds of the cannabinoid family, including tetrahydrocannabinol (THC) and cannabidiol (CBD). These cannabinoids bind to receptors called endocannabinoid receptors in the brain and throughout the body.
The psychoactive effects of cannabis are due to THC binding to CB1 receptors that are mostly present in the brain. The CB2 receptors are present on cells involved in the immune system. Cannabidiol (CBD), unlike THC, does not activate the reward system and does not result in intoxication (or a euphoric “high”). CBD has neuroprotective and anti-inflammatory properties and is used for medical purposes.
The amount of these cannabinoids depends on the specific strain of the cannabis plant.
Medical marijuana or medical cannabis refers to the use of marijuana for the treatment of a medical condition or to relieve its symptoms. Medical cannabis is especially effective in relieving chronic pain and seen as a much safer alternative to opiates due to its lower risk of addiction and almost negligible chances of overdose associated with medical marijuana.
Medical cannabis is also effective in alleviating nausea related to chemotherapy and in aiding weight gain for people with anorexia. There is also evidence supporting the effectiveness of cannabinoids in the treatment of multiple sclerosis-related muscle spasms and epileptic seizures.
Although many states have legalized the use of medical marijuana, the use of marijuana for medical purposes has not been approved by the federal government.
Synthetic marijuana or synthetic cannabinoids are chemical compounds that bind to cannabinoid receptors and are often chemically similar to tetrahydrocannabinol (THC) found in the cannabis plant. Besides having psychoactive effects, these drugs may also bind to other receptors in the brain and result in side effects.
These chemicals are often sprayed on dried plant material to give it the appearance of actual weed. These drugs are unregulated and can contain harmful ingredients that cause severe adverse effects, resulting in medical emergencies, organ damage and even death.
Methods of Use
There are various methods to consume marijuana, with smoking being one of the most common. Some of the methods include:
- Smoking. Rolling up marijuana in a cigarette or packing it into a pipe is one of the most common methods to smoke it is common. Marijuana smoke may also be inhaled using a water filter (bongs) or using a vaporizer.
- Oral ingestion. Marijuana may be mixed in food (edibles) such as baked goods and candies. It may also be brewed as a tea. Marijuana, when eaten, generally takes longer to produce the desired effects.
- Dabs. A newer form of marijuana ingestion involves the use of concentrated marijuana extracts referred to as dabs. These extracts are produced by extracting resins from the cannabis plant, and contain high concentrations of THC. These extracts are heated and inhaled. This form of marijuana intake can have more adverse effects due to the high concentrations of THC and is also associated with a higher risk of drug dependence.
Marijuana used for medical purposes may also be available in various forms including pills, oral drops or may even be injected.
Effects of Marijuana Use
The effects of marijuana depend on the dose and method of intake. Short-term use at low doses may reduce stress but a slightly higher dose may increase anxiety. Although short-term use at low doses may have only a few adverse effects, long-term use is associated with negative health and social consequences.
The time required for marijuana to have an effect depends on the method of intake. Smoking results in faster absorption of THC, whereas the effects are much slower when it is eaten.
Short-term effects of marijuana on the brain include:
- Alteration of senses and mild hallucinations
- Reduced anxiety
- Elevated mood and euphoria
- Altered sense of time and space
- Deficits in motor coordination
- Impaired intellectual abilities or cognitive deficits involving thinking, short-term memory, decision-making and attention
Short-term effects of marijuana use on the body include:
- Increased appetite
- Dryness of mouth
- Increased blood pressure and heart rate
Long-term marijuana use is generally associated with adverse effects. Some of the long-term effects of marijuana include:
- The development of physiological dependence on marijuana, with drug intake necessary to function normally
- Deficits in cognitive abilities and neuroanatomical aberrations in brain regions involved in these functions
Marijuana Street Names
Marijuana is commonly known as “weed,” but is referred to by different street names depending on the strain of the cannabis plant and the form. Some of the common street names of cannabis include:
- Mary Jane
Marijuana Side Effects
Using marijuana results in many different side effects such as impaired motor coordination and intellectual abilities, with larger doses having a potential to cause psychosis and cardiovascular toxicities. Long-term marijuana use can result in negative effects that impact the overall quality of life, including physical health, work and home life, and social activities.
Side effects on the body as a result of marijuana use include increased blood pressure and heart rate, nausea and impaired motor coordination. Marijuana intake increases heart rate by 20–50% within fifteen minutes and can increase the risk of a heart attack. The impaired motor abilities along with cognitive deficits induced by marijuana intoxication can also increase the chances of a car collision.
Long-term use of marijuana can have adverse effects on physical health including
- Increased risk of cardiovascular problems like myocardial infarction and cardiac arrhythmias.
- Various respiratory problems similar to those observed with smoking tobacco. These include bronchitis, pharyngitis, worsening of asthma. There is also mixed evidence for increased risk of nasopharyngeal carcinoma.
- Cycles of nausea, vomiting and dehydration. These symptoms together are referred to as cannabinoid hyperemesis syndrome.
- Physiological dependence and marijuana addiction.
The effects of marijuana use on the brain depend on the dose. There are several possible psychological effects of marijuana, including impaired intellectual abilities involving thinking, executive function, attention and working memory, as well as impaired brain development for adolescents. These cognitive deficits may last even after discontinuing use. The duration of these neurocognitive deficits is unclear.
At larger doses or due to long-term use marijuana may cause:
- Anxiety attacks
Long-term use of cannabis is associated with an increased risk of developing mood disorders and other substance abuse disorders. It can cause:
- Increased risk of anxiety and depression
- Increased risk of psychotic disorders like schizophrenia in individuals who have a predisposition for such disorders
- Increased risk of trying other drugs
Long-term use of marijuana is also associated with poor academic outcomes and an adverse impact on interpersonal relationships.
How Long Does Marijuana Stay in Your System?
Marijuana is rapidly metabolized after intake and THC tends to get absorbed by various organs like the liver, lungs, spleen and adipose tissue. The absorbed THC is gradually released back into the metabolism, resulting in a long half-life. The metabolites of THC are gradually eliminated over several weeks. The amount of time that marijuana may stay in an individual’s system depends on various factors, including frequency of use, THC levels in marijuana and an individual’s body fat (adipose tissue) levels.
Different tests show the presence of marijuana for different amounts of time:
Marijuana may be detected in the blood for only 3–4 hours. As a result, plasma samples are not frequently used to detect marijuana. However, there are studies that have demonstrated detectable levels for between 48–72 hours for some and a few weeks for others.
Marijuana can be detected in the urine for anywhere between a few days to a few weeks. Urine tests are one of the more commonly used methods for testing marijuana use.
Marijuana can be detected in hair follicles for up to 90 days. Besides getting incorporated into hair follicles via the bloodstream, marijuana may also be detectable in hair samples due to physical contact with the drug or exposure to second-hand marijuana smoke.
THC is secreted into breast milk and can result in the exposure of the infant to the compound. Marijuana can also alter the quality and quantity of breast milk. Exposure to marijuana through breast milk can have effects such as sedation, reduced muscle tone and may even impair brain development.
Is Marijuana Addictive?
Long-term use of marijuana results in the development of physical dependence on the drug. People who are dependent on marijuana feel the need to use the drug to function normally and may experience withdrawal symptoms if they stop using suddenly. Withdrawal symptoms can include irritability, insomnia, anxiety and drug cravings.
Approximately 1.5% (4.1 million Americans) of the individuals over the age of 12 had a marijuana use disorder, according to the NSDUH 2017 report. Around 9% of all people who use marijuana tend to become dependent on the drug with 17% of adolescents who use the drug being at risk of developing dependence. Although this number is lower than the statistics for heroin or cocaine, the number of people who use marijuana is much higher.
Drug addiction involves severe drug dependence with the inability to abstain from the use of a substance despite experiencing adverse physical and social effects. People who use marijuana or weed often satisfy these criteria for addiction and continue using the drug even while experiencing significant social, psychological and physical impairment.
The Recovery Village at Palm Beach at Baptist Health specializes in the treatment of substance use disorders and co-occurring mental disorders. Treatment for substance use disorders is tailored according to the symptoms and needs of each individual and is provided by clinical and medical staff with expertise in the treatment of such conditions. If you or someone you know suffers from marijuana addiction, reach out to The Recovery Village at Palm Beach at Baptist Health to learn how we can help.
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