From The National Institute of Health:
The National Institute of Drug Abuse
Revised September 2015
DrugFacts: Marijuana
When a person smokes marijuana, THC quickly passes from the lungs into the bloodstream. The blood carries the chemical to the brain and other organs throughout the body. The body absorbs THC more slowly when the person eats or drinks it. In that case, the user generally feels the effects after 30 minutes to 1 hour.
THC acts on specific brain cell receptors that ordinarily react to natural THC-like chemicals in the brain. These natural chemicals play a role in normal brain development and function.
Marijuana over activates parts of the brain that contain the highest number of these receptors. This causes the “high” that users feel. Other effects include:
• altered senses (for example, seeing brighter colors)
• altered sense of time
• changes in mood
• impaired body movement
• difficulty with thinking and problem-solving
• impaired memory
Long-term effects
Marijuana also affects brain development. When marijuana users begin using as teenagers, the drug may reduce thinking, memory, and learning functions and affect how the brain builds connections between the areas necessary for these functions.
Marijuana’s effects on these abilities may last a long time or even be permanent.
For example, a study showed that people who started smoking marijuana heavily in their teens and had an ongoing cannabis use disorder lost an average of eight IQ points between ages 13 and 38. The lost mental abilities did not fully return in those who quit marijuana as adults. Those who started smoking marijuana as adults did not show notable IQ declines (Meier, 2012).
What are the other health effects of marijuana?
Marijuana use may have a wide range of effects, both physical and mental.
Physical effects
• Breathing problems.Marijuana smoke irritates the lungs, and frequent marijuana smokers can have the same breathing problems that tobacco smokers have. These problems include daily cough and phlegm, more frequent lung illness, and a higher risk of lung infections. Researchers still do not know whether marijuana smokers have a higher risk for lung cancer.
• Increased heart rate.Marijuana raises heart rate for up to 3 hours after smoking. This effect may increase the chance of heart attack. Older people and those with heart problems may be at higher risk
• Problems with child development during and after pregnancy. Marijuana use during pregnancy is linked to increased risk of both brain and behavioral problems in babies. If a pregnant woman uses marijuana, the drug may affect certain developing parts of the fetus’s brain. Resulting challenges for the child may include problems with attention, memory, and problem-solving. Additionally, some research suggests that moderate amounts of THC are excreted into the breast milk of nursing mothers. The effects on a baby’s developing brain are still unknown.
Mental effects
Long-term marijuana use has been linked to mental illness in some users, such as:
• temporary hallucinations—sensations and images that seem real though they are not
• temporary paranoia—extreme and unreasonable distrust of others
• worsening symptoms in patients with schizophrenia (a severe mental disorder with symptoms such as hallucinations, paranoia, and disorganized thinking)
Marijuana use has also been linked to other mental health problems, such as:
• depression
• anxiety
• suicidal thoughts among teens
Is marijuana addictive?
Contrary to common belief, marijuana can be addictive. Research suggests that about 1 in 11 users becomes addicted to marijuana (Anthony, 1994; Lopez-Quintero 2011).This number increases among those who start as teens (to about 17 percent, or 1 in 6) (Anthony, 2006) and among people who use marijuana daily (to 25-50 percent) (Hall & Pacula, 2003).
How Does Marijuana Affect a User’s Life?
Compared to nonusers, heavy marijuana users more often report the following:
• lower life satisfaction
• poorer mental health
• poorer physical health
• more relationship problems
Users also report less academic and career success. For example, marijuana use is linked to a higher likelihood of dropping out of school (McCaffrey, 2010). It is also linked to more job absences, accidents, and injuries (Zwerling, 1990).
How can people get treatment for marijuana addiction?
Long-term marijuana users trying to quit report withdrawal symptoms that make quitting difficult. These include:
• grouchiness
• sleeplessness
• decreased appetite
• anxiety
• cravings
Behavioral support has been effective in treating marijuana addiction. Examples include therapy and motivational incentives (providing rewards to patients who remain substance free). No medications are currently available to treat marijuana addiction. However, continuing research may lead to new medications that help ease withdrawal symptoms, block the effects of marijuana, and prevent relapse.
Points to Remember
. . . (Please read online)]
drugabuse.gov/publications/drugfacts/marijuana
drugabuse.gov/about-nida/directors-page/messages-director/2012/09/marijuanas-lasting-effects-brain
PLEASE STAY AWAY FROM MARIJUANA! Thank you.