The dangers of teens using marijuana
September 25, 2014
Science Daily/Loyola University Health System
Whether states should legalize marijuana for recreational and medical use is a hot topic across the country. As the debates continue a potentially dangerous environment is being created where more preteens, teens and young adult are beginning to use the substance with the feeling that it is safe. In fact, 36 percent of all seniors in high school and 7 percent of eighth-graders report using the drug in the past month, according to a recent study. Though public perception is that marijuana is a harmless drug, research is showing it can have a damaging impact on developing brains and may lead to life-long addiction.
"Teens are seeing marijuana as a safe substance, but its effects on the adolescent brain can be dangerous, especially if there is heavy use. As the stigma of marijuana use becomes less the number of teens using the drug has increased. More high-schoolers in the U.S. now smoke marijuana than they do cigarettes," said Garry Sigman, MD, director of the adolescent medicine division at Loyola University Health System and professor in the Department of Pediatrics at Loyola University Chicago Stritch School of Medicine.
Marijuana is an addictive substance and, according to Sigman, adolescents are 2-4 times more likely to become dependent on the drug within two years after first use compared with adult users.
"Marijuana is the most common substance addiction being treated in adolescents in rehabilitation centers across the country. Like all addictive substances, marijuana is used to lessen uncomfortable feelings like anxiety and depression. Because the type of addiction is seen as less 'intense' in comparison to other substances such as cocaine or heroin, many people don't realize that marijuana can cause dependence and has a withdrawal syndrome," Sigman said.
Some adolescents use marijuana only occasionally because of peer pressure at a party or in a social setting, but others self-medicate with marijuana to cope with emotions and stress. One of the signs of a substance-use disorder is when drugs are used often to cope with uncomfortable feelings.
Addiction isn't the only hazard for adolescents when it comes to smoking marijuana. Research shows that heavy use can lead to neurotoxicity and alternations in brain development leading to: • Impairment in thinking • Poor educational outcomes and perhaps a lower IQ • Increased likelihood of dropping out of school • Symptoms of chronic bronchitis • Increased risk of psychosis disorders in those who are predisposed.
"Parents should inform themselves about the scientific facts relating to marijuana and the developing brain and be able to discuss the topic calmly and rationally. They need to explain that the dose of the drug in a 'joint' is three to four times higher than in years past, and that if the parents occasionally used during their lives, they now know that the risk is present if used before adulthood," Sigman said.
https://www.sciencedaily.com/releases/2014/09/140925150606.htm
Reversing the negative effects of adolescent marijuana use
September 12, 2017
Science Daily/University of Western Ontario
Researchers at Western University have found a way to use pharmaceuticals to reverse the negative psychiatric effects of THC, the psychoactive chemical found in marijuana. Chronic adolescent marijuana use has previously been linked to the development of psychiatric diseases, such as schizophrenia, in adulthood. But until now, researchers were unsure of what exactly was happening in the brain to cause this to occur.
"What is important about this study is that not only have we identified a specific mechanism in the prefrontal cortex for some of the mental health risks associated with adolescent marijuana use, but we have also identified a mechanism to reverse those risks," said Steven Laviolette, professor at Western's Schulich School of Medicine & Dentistry.
In a study published online today in Scientific Reports the researchers demonstrate that adolescent THC exposure modulates the activity of a neurotransmitter called GABA in the prefrontal cortex region of the brain. The team, led by Laviolette and post-doctoral fellow Justine Renard, looked specifically at GABA because of its previously shown clinical association with schizophrenia.
"GABA is an inhibitory neurotransmitter and plays a crucial role in regulating the excitatory activity in the frontal cortex, so if you have less GABA, your neuronal systems become hyperactive leading to behavioural changes consistent with schizophrenia," said Renard.
The study showed that the reduction of GABA as a result of THC exposure in adolescence caused the neurons in adulthood to not only be hyperactive in this part of the brain, but also to be out of synch with each other, demonstrated by abnormal oscillations called 'gamma' waves. This loss of GABA in the cortex caused a corresponding hyperactive state in the brain's dopamine system, which is commonly observed in schizophrenia.
By using drugs to activate GABA in a rat model of schizophrenia, the team was able to reverse the neuronal and behavioural effects of the THC and eliminate the schizophrenia-like symptoms.
Laviolette says this finding is especially important given the impending legalization of marijuana in Canada. "What this could mean is that if you are going to be using marijuana, in a recreational or medicinal way, you can potentially combine it with compounds that boost GABA to block the negative effects of THC."
The research team says the next steps will examine how combinations of cannabinoid chemicals with compounds that can boost the brains GABA system may serve as more effective and safer treatments for a variety of mental health disorders, such as addiction, depression and anxiety.
https://www.sciencedaily.com/releases/2017/09/170912134809.htm