What are the health risks of marijuana use in teenagers?

Health Risks of Marijuana Use in Teenagers

Marijuana use during adolescence poses significant health risks including adverse cardiovascular effects, negative impacts on brain development, increased risk of mental health disorders, and impaired cognitive function. 1, 2

Cardiovascular Risks

• THC (the psychoactive component in marijuana) acts on cannabinoid receptors causing significant cardiovascular effects through:

  • Beta-adrenergic stimulation
  • Alterations in vascular tone
  • Changes in cardiac output and peripheral resistance 1

• Specific cardiovascular risks include:

  • Tachycardia (increased heart rate)
  • Blood pressure changes (both hypertension and orthostatic hypotension)
  • Increased risk of myocardial infarction and stroke
  • Dose-dependent stroke risk, with usage more than once weekly significantly elevating risk 1

• These risks are particularly concerning for teenagers as hospitalizations for stroke in younger cannabis users (18-38 years) are increasing 1

Neurological and Mental Health Impacts

• Marijuana use during adolescence has been associated with several adverse mental health outcomes:

  • Increased incidence of addiction and comorbid substance use
  • Higher rates of suicidality
  • New-onset psychosis
  • Depression and anxiety 2

• The risk is heightened due to the developing adolescent brain, with potential for:

  • Disruption to the brain's reward system
  • Impaired memory and cognition
  • Structural brain changes 3

• Cannabis use disorder is a significant risk, with altered neurodevelopment being a major concern in the adolescent population 4

Academic and Functional Impacts

• Negative impacts on cognition and academic performance have been observed in teenage marijuana users 2

• Frequent teenage cannabis use (weekly or daily) is associated with:

  • Problematic substance use in young adulthood
  • Increased delinquency
  • Poorer functional well-being by age 20
  • Financial difficulties
  • Social exclusion
  • Higher likelihood of not being in education, employment, or training 5

Respiratory and Physical Health Concerns

• Smoking cannabis has negative impacts on the pulmonary system as it acts as a respiratory irritant 3

• Vaping cannabis, increasingly popular among teenagers, delivers higher concentrations of psychoactive compounds, potentially increasing health risks 3

• The average concentration of THC in cannabis products has increased dramatically (from 9% in 2008 to 17% in 2017), with concentrates containing up to 70% THC, significantly increasing risk of adverse effects 1

Concerning Trends

• Changes in marijuana legalization coincide with:

  • Decreased perception of harmfulness among youth
  • Increased use among teenagers 2

• Many teenagers do not recognize the health risks of cannabis use, including increased risk of motor vehicle accidents 3

• Some adolescents self-medicate with marijuana for health concerns including:

  • Depression, anxiety, and stress
  • Sleep difficulties
  • Concentration problems
  • Physical pain 6

This self-medication approach is particularly concerning as it may delay proper medical treatment and lead to cannabis dependence.

Clinical Implications

• All teenagers should be screened for cannabis use 3

• Healthcare providers should assess cardiovascular risk factors in teenagers using marijuana and monitor for signs of tachycardia, hypertension, or orthostatic hypotension 1

• Education about cannabis risks should be age-specific, evidence-based, and start in elementary education, continuing through high school 3

• Screening for underlying mental health disorders is essential, as these may contribute to or be exacerbated by cannabis use 3