Legalization of medical and recreational marijuana has led to increased usage of the drug in many places around the world. So how dangerous is cannabis, really, and what can be done to protect young people from starting to use it? For those already using or addicted, what can be done to help them into and through recovery? Presenter Marc Myer, MD, is the director of the Hazelden Betty Ford Foundation's Health Care Professionals Program in Center City, Minnesota. Amanda Klinger, PsyD, LP, is a Senior Clinician who works with adolescents and young adults at one of the residential units on the Hazelden Betty Ford campus in Plymouth, Minnesota. Watch the recorded webinar now. Key Takeaways: Marijuana has been used spiritually and medicinally since around 3000 B.C., and is currently used by 160 million people worldwide. A single marijuana plant contains over 420 chemicals. The primary psychoactive chemical is marijuana is THC. The average concentration of THC in marijuana in 1983 was less than 4%. In 2012, it was 15%. Physical effects of marijuana use include relaxation, sedation, pain relief, increased appetite, minor coordination loss, red eyes, and pupillary dilation. Marijuana is the most commonly used drug in the U.S. According to the National Survey on Drug Use and Health, 34% of Americans have used marijuana in their lifetime; 4.8% in the past month. That number is on the rise among every demographic. Marijuana use peaks between 18 and 25 years of age. Marijuana use among young people goes up as the perceived risks of marijuana use decreases. Marijuana can be addictive, leading to both psychological and physiological dependence. Synthetic cannabinoids are more potent, less reliable, and linked to more side-effects. Medical marijuana is legal in many states, but most physicians oppose its use. Young adults who use marijuana are more likely to use other drugs. Short-term effects of marijuana use (dose-related) Slight confusion Mental separation from environment Poor concentration Drowsiness Giddiness Increased alertness Paranoia/de-personification Stimulant or depressant Short-term memory and attention impairment Motor skills and reaction time impairment Driving impairment Decision-making and executive function impairment Effects of long-term marijuana use include: Altered brain function in the prefrontal cortex, cerebellum, and hippocampus Risky decision-making Cognitive impairment for those who start in adolescence May increase risk of chronic mental disorders in otherwise healthy individuals Respiration symptoms Distorted sense of time Withdrawal symptoms when quitting Special concerns with adolescent use include: Associated with less stability in adult social roles Earlier use related to more involvement in adult drug use Acute effects on memory and learning Associated with poorer academic performance Escalates to problematic use more quickly than with older initiators According to a 2013 survey of 18- to 25-year-olds (commissioned by the Hazelden Betty Ford Foundation): 42% have used marijuana 20% of those use it daily 60% of those use it rarely 35% started using between 14- to 16-years-old 36% started using between 17- to 19-years-old 72% of children whose parents used marijuana have used it 20% of children whose parents never used marijuana have used it 40% think it is not addictive (not true) 37% think it does not damage the brain (not true) 33% who use marijuana have driven high Watch the recorded webinar Marijuana: Don't Get Stuck in the Weeds. Learn more about upcoming webinars or browse our webinar archives.