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SPECT brain scan of a normal brain

Brain scan of a normal brain

SPECT brain scan of teenage marijuana user

Brain scan of 16 yr old marijuana user  

Brain scan of teenage marijuana user

Brain scan of 18 yr old marijuana user

 

 

 

 

It’s a myth that marijuana is safe.  While CBD has proven benefits, THC’s effect on adolescents can lead to psychosis and long-term cognitive impairment.  High THC doses has a profound negative effect.  Marijuana’s effects on the brain has been researched internationally for decades.  It’s not new information. I’ve found parents don’t realize this, and attribute their child’s behavior to other things.  Even though it CBD has proven benefits, high levels of THC is toxic, with uniquely destructive effects on young brains under age 25.

Thanks to plant breeding, THC has reached toxic levels in marijuana

One researcher studied marijuana use in both mentally ill and normal adult test subjects.  He wrote, “When THC (tetrahydrocannabinol) was administered in one trial, it caused both patients and controls to experience transient increases in cognitive impairments and schizophrenia-like… symptoms.”

Marijuana legalization has deeply concerned psychiatrists and other medical providers for children, teenagers, and young adults.  Why?  Young brains normally undergo radical changes from puberty to at least age 25.  Excessive neuron circuits are “pruned” if they’re rarely used to reduce the brain’s energy demand. Think about it. A lot of nonsensical teenage behavior can be explained by the loss of duplicates. THC comes in and overpowers the delicate chemistry that guides the pruning process.  THC is like using a blowtorch to light a candle.

Numerous research summaries are appended below and key messages are highlighted if you don’t want to read all the way through.  I found this one quote extraordinarily sad.  I wish other parents knew.

“Increasing levels of cannabis use at ages 14-21 resulted in lower levels of degree attainment by age 25, lower income at age 25, higher levels of welfare dependence, higher unemployment, lower levels of relationship satisfaction, and lower levels of life satisfaction.”

I worked with adolescents in residential care and in the juvenile justice system who regularly used marijuana when they could.  A young man on my caseload grew noticeably depressed after he started smoking regularly, and he became anxious and mistrusting–paranoia–and hostile to caseworkers .  He said that smoking helped him feel better, but he couldn’t observe what I and other social workers observed over time. Smoking marijuana was briefly relieving him of its own side-effects.

“Medical marijuana” or cannabis, is CBD not THC.

  A note on medical marijuana – The plant Cannabis sativa has two substances of interest:

  1. cannabidiol (CBD) – the molecule considered safe, and is approved by the American Medical Association;
  2. tetrahydrocannabinol (THC) – the molecule responsible for the high and which causes psychotic symptoms at higher doses.

Please share this information with other parents.   The same warnings parents teach about alcohol and street drugs also apply to marijuana.  If it’s difficult to stop your child from using, especially in states where it is legal, you may have options to reduce use.  Some have provided only CBD oil instead because their child found it more acceptable than psychiatric treatment.  And CBD does reduce depression and anxiety in many.

–Margaret

 


Proof cannabis DOES lead teenagers to harder drugs
Daily Mail, London U.K., June 7, 2017

“The study of the lives of more than 5,000 teenagers produced the first resounding evidence that cannabis is a gateway to cocaine, amphetamines, hallucinogens and heroin.” Read the full story  “Teenagers who regularly smoke cannabis are 26 times more likely to turn to other drugs by the age of 21.  It also discovered that teenage cannabis smokers are 37 times more likely to be hooked on nicotine and three times more likely to be problem drinkers than non-users of the drug.”


Legal cannabis laws impact teen use
The Geisel School of Medicine at Dartmouth, NH, June 27, 2017

‘A new study has found that adolescents living in medical marijuana states with a plethora of dispensaries are more likely to have tried new methods of cannabis use, such as edibles and vaping, at a younger age than those living in states with fewer dispensaries. ” …As cannabis legalization rapidly evolves, in both medical and recreational usage, understanding the laws’ effect on young people is crucial because of its adverse effects, and possesses an inherent elevated risk of developing an addiction.


Marijuana Can Permanently Lower IQ in Teens
Duke University and King College (London), August 2012

Teens who regularly smoke marijuana are putting themselves at risk of permanently damaging their intelligence as adults, and are also significantly more likely to have attention and memory problems later in life, than their peers who abstained, according to a new study conducted by Duke University and London’s King’s College. This study is among the first to distinguish between cognitive problems the person might have had before using marijuana, and those that were caused by the drug..

The research found that adults who started smoking pot as teenagers and used it heavily, but quit as adults, did not regain their full mental powers. In fact, “persistent users” who started as teenagers suffered a drop of eight IQ points at the age of 38, compared to when they were 13.  Researchers noted that many young people see marijuana as a safer alternative to tobacco. A recent “Monitoring the Future” study found that, for the first time, more American high school students are using marijuana than tobacco. Lead researcher Madeline Meier, a post-doctoral researcher at Duke University, said, “Marijuana is not harmless, particularly for adolescents.”


Risks of increasingly potent Cannabis: The joint effects of potency and frequency
Joseph M. Pierre, MD; Current Psychiatry. 2017 February;16(2):14-20

Cannabis at a young age (age <15 to 18) increases the risk of developing a psychotic disorder.  The accumulated evidence to date is strong enough to view the psychotic potential of Cannabis as a significant public health concern, especially a high-potency Cannabis (HPC) form of hash oil known as Cannabis “wax” or “dabs” that contains as much as 90% THC. Preliminary anecdotal evidence supports the plausibility of hyper-concentrated forms being more psycho-toxic than less potent forms.  Of great concern when it comes to teens, HPC comes in very appealing forms (baked goods, candy, and drinks).  Full article here.


“Woody Harrelson quit; What happens to your body after a stoner quits smoking weed.”
Expect the following if you child attempts to quit or quits marijuana, and give them lots of love and support!  Dr. Stuart Gitlow and Dr. Joseph Garbely explain what happens to them.  Read the full article here.

  • They miss and crave it at first
  • They get anxious
  • They feel feelings again
  • It’s going to be uncomfortable for months, even a year

Marijuana Use Linked with Poor Depression Recovery
Journal of Affective Disorders; ePub 2017 Feb 13; Bahorik, et al

Marijuana use is common and associated with poor recovery among psychiatry outpatients with depression a recent study found. Researchers evaluated 307 psychiatry outpatients with depression, and past-month marijuana use for a substance use intervention trial. They found:

  • Marijuana use worsened depression and anxiety symptoms. It also led to poorer mental health functioning.
  • Medical marijuana (26.8%; n=33) was associated with poorer physical health functioning.

Keeping Teenagers Safe In Vehicles:  Alcohol use is down but marijuana use is up
O’Malley, P. & Johnson, American Journal of Public Health. Nov. 2013, Vol 103, No. 11.

Driving accidents remain the number one cause of mortality among American teenagers. Alcohol use is often involved, and more recently, distracted driving as a result of cell phones is a contributor. A recent analysis has found that drinking and driving has decreased among teenagers, but using marijuana and driving has increased.”  In this longitudinal study, a sample of 22,000 12th grade students from high schools across the country were questioned over a ten-year period, from 2001-2011. They showed an increase over the 10-year period in either being the driver or passenger of a driver who had just used marijuana. Specifically, 28% reported doing so within the past two weeks.  Marijuana use can impact drivers as much as alcohol.


Early Marijuana Use Heightens Psychosis Risk in Young Adults (summary)
John McGrath MD, Rosa Alati MD Archives of General Psychiatry, published online March 1, 2010,
MedscapeCME: Psychiatry and Mental Health

“Early cannabis use increases the risk of psychosis in young adults,” reports lead investigator John McGrath, MD, of Queensland Centre for Mental Health Research in Brisbane, Australia.  “Apart from having an increased risk of having a disorder like schizophrenia, the longer the young adults reported since their first cannabis use, the more likely they were to report isolated symptoms of psychosis.”

Investigators assessed 3801 study participants at ages 18-23 years, identifying first marijuana use and three psychosis-related outcomes:  non-affective disease, hallucinations, and the Peters et al Delusions Inventory Score.  “Psychotic disorders are common and typically affect 1 or 2 people of every 100” Dr. McGrath said, “…(I) was surprised that the results were so strong and so consistent…  We need to think about prevention.”

Results mirror those of another study conducted by Michael Compton MD, published in the American Journal of Psychiatry (November 2009), where investigators looked at 109 patients in a psychiatric unit and found that daily marijuana and tobacco use was common.  Of those who abused cannabis, almost 88% were classified as weekly or daily users before the onset of psychosis.

Emma Barkus, PhD, from the University of Wollongong in New South Wales, Australia, says other studies suggest that those who are engaging in risk behaviors about the age of 14 years are more likely to persist as they get older, adding further support to the role of cannabis use in predicting earlier psychoses.


Evidence Accumulates for Links Between Marijuana and Psychosis (summary)
Michael T. Compton, MD, MPH – Assistant Professor, Emory University School of Medicine, Department of Psychiatry and Behavioral Sciences, Atlanta, Georgia, 2008

Cannabis is the most abused illicit substance in the general US population, and the most abused illegal drug among individuals with schizophrenia.  This literature reviewed studies that examined (1) associations between cannabis use and clinical manifestations of psychosis, and (2) the biologic plausibility of the observed links.

The initiation of cannabis use among those with psychotic disorders often precedes the onset of psychosis by several years.  Cannabis use in adolescence is increasingly recognized as an independent risk factor for psychosis and schizophrenia.  Teens progress to daily cannabis use was associated with the age when they started.

Study evidence also supported biological links between cannabis use and psychosis.  In the brains of heavy users, interactions with specific cannabinoid receptors are distributed in brain regions implicated in schizophrenia.  Other studies report elevated levels of endogenous cannabinoids in the blood and cerebrospinal fluid of patients with schizophrenia.  When THC (tetrahydrocannabinol) was administered in one trial, it caused both patients and controls to experience transient increases in cognitive impairments and schizophrenia-like positive and negative symptoms.


Chronic toxicology of cannabis.  (summary)
Reece, Albert Stuart; Clinical Toxicology (Philadelphia, PA.)   vol. 47  issue 6, Jul  2009 . Medical School, University of Queensland, Highgate Hill, Brisbane, QLD, Australia.

 Findings: There is evidence of psychiatric, respiratory, cardiovascular, and bone toxicity associated with chronic cannabis use.  Cannabis is implicated:

  • In major long-term psychiatric conditions including depression, anxiety, psychosis, bipolar disorder;
  • Respiratory conditions include reduced lung density, lung cysts, and chronic bronchitis;
  • elevated rates of myocardial infarction and cardiac arrythmias;
  • linked to cancers at eight sites, including children after in utero maternal exposure.

Marijuana Use, Withdrawal, and Craving in Adolescents (summary)
Kevin M. Gray, MD, Assistant Professor in the youth division of the Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina in Charleston.

Findings in the literature survey:  Initiation of marijuana use typically occurs during adolescence.  Recent data indicate that in the United States, 42% of high school seniors have tried marijuana; 18% have used it in the past 30 days; and 5% use it daily.  Among adolescents aged 12 to 17, 3.6% met criteria for cannabis use disorder (abuse or dependence) and 2% met criteria for cannabis dependence.

More than half (51%) of adolescents reported that marijuana is fairly or very easy to obtain.  Ironically, this ready availability may be a “reverse gateway” from marijuana use to cigarette use to nicotine dependence.  Earlier initiation is associated with problem-related marijuana use: “hard” drug use, poly-drug use, and academic failure.  Using marijuana once per week or more during adolescence is associated with a 7-fold increase in the rate of daily marijuana use in young adulthood.  Cannabis dependence increases the risk factors for impaired driving and delinquent behavior.  Chronic marijuana use is associated with impaired immune function, respiratory illnesses, cognitive problems, and motivational impairment. 

There is a debate whether marijuana use begins as “self-medication” for psychiatric disorders, or whether habitual marijuana use can predispose some individuals to psychiatric symptoms.

Social anxiety disorder in adolescence is associated with 6.5-times greater odds of subsequent cannabis dependence, and vice versa, frequent marijuana use during adolescence appears to increase the risk of subsequent development of anxiety and depressive disorders.  The prevalence of cannabis abuse is 2 to 3 times greater among adolescents who have major depression.  Also linked in both directions: conduct disorder predicts marijuana and other substance use, while early-onset marijuana use predicts conduct disorder.

Five treatment regimes were studied: motivational enhancement/cognitive-behavioral therapy (MET/CBT), family education and therapy intervention, a community reinforcement approach, and multidimensional family therapy.  All resulted in positive but modest outcomes, with MET/CBT and community reinforcement treatments being most cost-effective.

Emerging evidence indicates rewards for marijuana abstinence may be positive.  Multi-systemic therapy, an intensive approach that incorporates individual, family, and community components, has demonstrated effectiveness among delinquent adolescents.

Withdrawal: Marijuana withdrawal symptoms are a constellation of emotional, behavioral, and physical symptoms that include anger and aggression, anxiety, decreased appetite and weight loss, irritability, restlessness, and sleep difficulty, which result specifically from withdrawal of marijuana’s psychoactive ingredient, THC.  Less frequent but sometimes present symptoms are depressed mood, stomach pain and physical discomfort, shakiness, and sweating.  Onset of withdrawal symptoms typically occurs within 24 hours of cessation of THC, and symptoms may last days to approximately 1 to 2 weeks.

Craving: Patients’ craving of marijuana is evidenced after presenting them with cues associated with marijuana (e.g. sight or smell of the substance, films of drug-taking locations, and drug-related paraphernalia).   Exposure to cues leads to robust increases in craving, along with modest increases in perspiration and heart rate.  Cue reactivity can predict drug relapse.

Craving and withdrawal symptoms interfere with successful cessation of use and sustained abstinence.  In addition, medications are often used to target withdrawal from substances, such as benzodiazepines for alcohol dependence and clonidine and buprenorphine for opioid dependence. These medications could be combined with psychosocial interventions, or developed to complement concurrent psychosocial treatments.


Legalization of Marijuana: Potential Impact on Youth (summary)
Alain Joffe, MD, MPH, W. Samuel Yancy, MD the Committee on Substance Abuse and Committee on Adolescence – PEDIATRICS Vol. 113 No. 6 June 2004, pp. e632-e638

Scientists have demonstrated that the emotional stress caused by withdrawal from marijuana is linked to the same brain chemical that has been linked to anxiety and stress during opiate, alcohol, and cocaine withdrawal.  THC stimulates the same neurochemical process that reinforces dependence on other addictive drugs.  Current, well known, scientific information about marijuana shows the cognitive, behavioral, and somatic consequences of acute and long-term use, which include negative effects on short-term memory, concentration, attention span, motivation, and problem solving.  These clearly interfere with learning, and have adverse effects on coordination, judgment, reaction time, and tracking ability.  http://pediatrics.aappublications.org/cgi/content/full/113/6/e632


The Past, Present, and Future of Medical Marijuana in the United States (summary)
By John Thomas, JD, LLM, MPH, Professor of advanced law and medicine, civil procedure, and commercial law at the Quinnipiac University College of Law, Hamdon, Connecticut, January 6, 2010

Cannabidiol (CBD) is considered safe and has a variety of positive benefits, and this component should be legalized.  However, the other narcotic component in marijuana, tetrahydrocannabinol (THC), is responsible for the high, and too much may not be a good thing because it can produce psychotic symptoms in people.


 Medical Marijuana:  The Institute of Medicine Report (summary)
Ronald Pies, MD, Editor in Chief – Psychiatric Times. Vol. 27 No. 2 , January 6, 2010
Marijuana is not a completely benign substance. It is a powerful drug with a variety of effects.  However, except for the harms associated with smoking, the adverse effects of marijuana use are within the range of effects tolerated for other prescription medications. Cannabinoids can induce acute transient psychotic symptoms or an acute psychosis in some individuals… (but it is unclear) what makes some individuals vulnerable to cannabinoid-related psychosis.  There is a pressing need for more high-quality research in the area of medical marijuana and cannabinoid use.

 Link Between Cannabis Use and Psychosis Onset at a Younger Age (summary)
Ana Gonzales MD, Santiago Apostol Hospital in Vitoria, Spain, Journal of Clinical Psychiatry. August 2008

Researchers found a strong and independent link between cannabis use and the onset of psychosis at a younger age, regardless of gender or the use of other drugs.  The link is related to the amount of cannabis used.  “The clinical importance of this finding is potentially high,” Dr. Gonzalez-Pinto given that cannabis use is extremely prevalent among young people… estimates of the attributable risk suggest that the use of cannabis accounts for about 10 percent of cases of psychosis. “The findings showed a significant gradual reduction in the age at which psychosis began that correlated with an increased dependence on cannabis. Compared with nonusers, age at onset was reduced by 7, 8.5, and 12 years among users, abusers, and dependents, respectively, the researchers report.

Cannabis use and later life outcomes. (summary)
Fergusson DM, Boden JM, Addiction;  Pages: 969-76;  Volume(Issue): 103(6), June 2008

A longitudinal study of a New Zealand birth cohort tracked subjects to age 25 years.  The research tracked university degree attainment to age 25; income at age 25, welfare dependence during the period 21-25 years, unemployment between 21-25 years, relationship quality, and life satisfaction.  They adjusted for confounding factors:  childhood socio-economic disadvantage, family adversity, childhood and early adolescent behaviors, cognitive ability, mental health, and substance use. The findings were statistically significant.  Increasing levels of cannabis use at ages 14-21 resulted in lower levels of degree attainment by age 25, lower income at age 25, higher levels of welfare dependence, higher unemployment, lower levels of relationship satisfaction, and lower levels of life satisfaction.


Doctors:  Pot Triggers Psychotic Symptoms (summary)
May 1, 2007
Aetna Intelihealth – Mental Health

 LONDON — New findings show physical evidence of the drug’s damaging influence on the human brain.  In some people, it triggers temporary psychotic symptoms including hallucinations and paranoid delusions. Two of the active ingredients of cannabis: cannabidiol (CBD) made people more relaxed.  But second ingredient: tetrahydrocannabinol (THC) in small doses produced temporary psychotic symptoms in people, including hallucinations and paranoid delusions. According to Dr. Philip McGuire, a professor of psychiatry at King’s College, London, THC interfered with activity in the inferior frontal cortex, a region of the brain associated with paranoia. “THC is switching off (a chemical) regulator,” McGuire said, “effectively unleashing the paranoia usually kept under control by the frontal cortex.” In another study, Dr. Deepak Cyril D’Souza, an associate professor at Yale University School of Medicine, and colleagues tested THC on 150 healthy volunteers and 13 people with stable schizophrenia. Nearly half of the healthy subjects experienced psychotic symptoms when given the drug.  Unfortunately, the results for the schizophrenic subjects was so much worse that researchers scrapped adding additional schizophrenic subjects to the study.  The negative impact was so pronounced, researchers felt it was unethical to continue the tests. “One of the great puzzles is why people with schizophrenia keep taking the stuff when it makes the paranoia worse,” said Dr. Robin Murray, a professor of psychiatry at King’s College in UK.  She theorized that schizophrenics may mistakenly judge the drug’s pleasurable effects as outweighing any negatives. 

7 Comments

  • Victoria says:

    Great information…I’m happy that my kids have never been near drugs, and I hope and pray they never will be!
    I recently read an article that discussed giving marijuana to children with ADHD. Doctors actually prescribing the drug to kids as young as five years old! – Unbelievable!

  • Margaret says:

    Hi Victoria. I’ve heard about giving MJ to ADHD kids and those with anxiety to ease their symptoms. Hey, why not cigarettes which also work, or alcohol? But who honestly thinks these substances are OK for children and teens? I’ve seen MJ have a temporary benefit in adults. It’s short-lived and the potential side-effects are addictions, which those with ADHD are especially prone, or cancers–the loss of brain function, as shown in SPECT brain scans, affect all users.

  • Ranen says:

    I first smoke marajuana in the 4th grade which makes me like 9 years old. I smoked 3 to 4 times on a daily basis. I am diagnosed bipolar 1 and schizoeffective. I never had problems with anything untill i was 22. I can’t even smoke marajuana anymore because the meds that i currently take now, resperidone and lamictal. I am smart obtaining a a 3.0 gpa throughout highschool. My mothers father had schitzophrenia. So how can any scientific data prove it causes psychosis, marajuana. Everyone i know smokes marajuana and there doing just fine. We all are different. Its like a that person can drink 2 beers and not feel a thing, yet I cant drink 2 beers or I’ll pass out. I believe it has to do with a persons body chemistry wether they feel positive or negative effects of any drug. I believe all drugs have there pros and cons, legal and illegal drugs.

  • FIDELINA RUIZ says:

    DON”T KNOW WHAT TO DO ANYMORE.

  • devin says:

    please do not think im saying this information is invalid but when you say the people who use marijuana as a teen are more likely to not pursue higher education. well going through education is not the only way to become more intelligent and should not be considered what you should do now. im a very deep thinker and i have learned to educate myself. i was able to discover the teachings that budda taught without knowing one thing about buddism(sorry for mispelling). and about your side effects part, every single thing in the world has side effects. stress, the food we eat, and even what we do during the whole day. have you ever seen some have a heart attack from cannabis? no, have you seen people have a heart attack from stress that people have no control over? yes. my grandfather had a heart attack and broke his shoulder cause he fell of a latter and it was due to the stress he was under. marijuana should be the least of concerns when it comes to bad things for human beings cause there are so many other factors and things that people endure that make them die and when people say marijuana destroys there life the only way that happens is cause it is illegal and people kill themselves over it cause if it was legal do you think people will buy from a dealer when they could to a nice government cleared company building and buy from a licensed vendor or store owner. thank you

    • Margaret says:

      Hello Devin,
      Thank you for your comments. This blog is for people who want to know how to raise a teen with serious behavioral difficulties (usually from a mental disorder), keep them safe, and help them grow to a functional adulthood. In the case of young people, the side effects of marijuana (psychosis) create as serious a life threatening situation as a heart attack, because psychosis leads to suicidal thoughts and suicide (or severe depression, anxiety, extreme paranoia). I know this from my own child. My main purpose was to warn parents and caregivers that marijuana has a uniquely serious and devastating impact on their teen because of their vulnerability to psychosis. You are correct that many substances have negative side effects, but most people think marijuana is completely safe or that side effects are mild. They are not. I look at it this way, a large part of our population (about 80%) can drink alcohol but within limits so that it doesn’t disable them, undermine their lives, or kill them. But for that remaining 20% or so, alcohol can destroy everything important to them, livelihood, love, health, and life (such as from driving intoxicated). These 20% can’t EVER drink alcohol. The same is true for marijuana and our affected children, except the resulting psychosis is far more deadly than alcoholism. A parent needs to know this. Marijuana triggers and worsens mental illness–a devastating condition for sufferers and their families.
      Margaret