DESCRIPTION

• Cannabis (also known as marijuana) is one of the most commonly used psychoactive substances worldwide and the most commonly used illicit substance in all ages in the U.S.
  • The medical use of cannabis is U.S. Food and Drug Administration (FDA)-approved in children only for specific forms of epilepsy and in adults for chemotherapy-induced nausea/vomiting and AIDS-related anorexia.
  • Cannabis refers to the dried leaves, flowers, stems, seeds, and extracts from the Cannabis sativa or Cannabis indica plant.
  • Cannabis is available as natural cannabinoids and synthetic analogues, including δ9-tetrahydrocannabinol (THC), the most psychoactive cannabinoid, cannabidiol (CBD), and cannabinol (CBN).
• The amount of THC in cannabis has steadily climbed over the past decades, with today’s cannabis containing 3 times the concentration of THC compared to 25 years ago.
• Cannabis can be used in a variety of ways, including smoking (alone or in combination with other substances such as tobacco), vaping, ingesting (edibles, beverages, tinctures), dabbing (vaporizing cannabinoid oil), and applying topical cream.
• Alternative names for cannabis include the following:
  • Natural: “marijuana,” “pot,” “grass,” “dope,” “MJ,” “Mary Jane,” “doobie,” “hooch,” “weed,” “hash,” “reefer,” “bud,” and “ganja”
  • Synthetic: “K2,” “spice,” “crazy monkey,” “chill out,” “spice diamond,” “spice gold,” and “chill X”
• Complications of cannabis use include acute intoxication, including cannabinoid hyperemesis syndrome (CHS), dependence/abuse, and withdrawal.
  • CHS is characterized by recurrent and stereotypical episodes of vomiting triggered by chronic, heavy cannabis use with intervening periods of normal health.
• Cannabis use disorder refers to the inability of an individual to stop using marijuana despite the associated health and social problems.
• Cannabis use disorder and cannabis withdrawal syndrome are diagnoses in the Diagnostic and Statistical Manual of Mental Disorders, 5th edition (DSM-5).
  • Related diagnoses include cannabis intoxication delirium, cannabis-induced psychotic disorder, cannabis-induced anxiety disorder, and cannabis-induced sleep disorder.
• CHS diagnostic criteria are specified in the Rome IV Diagnostic Criteria.

EPIDEMIOLOGY

• Cannabis use disorder develops in approximately 10% of regular cannabis users and up to 50% of chronic daily users.
• Cannabis use disorders are more common in males than females.
• In the United States, approximately 5% of people ≥12 years of age meet the criteria for a cannabis use disorder.
  • 1 in 6 people who start using cannabis before the age of 18 years become addicted.

• Between 2005 and 2009, 985 unintentional exposures to children (median age of 1.7 years) were reported in the United States. States legalizing cannabis have had a 20-fold increase in calls to poison centers and admissions to critical care units for pediatric exposure since passing legislation.
• Of U.S. high school students surveyed with the 2019 Youth Risk Behavior Survey (YRBS), 22% reported current cannabis use and 37% reported lifetime use.
  • 18% reported using it ≥40 times in the past 30 days.

GENERAL PREVENTION

Avoid cannabis use and exposure by keeping all cannabis products secure and out of reach of minors.

PATHOPHYSIOLOGY

• Exposure
  • Young children with cannabis intoxication typically ingest cannabis products found in the home.
  • Adolescents most commonly become intoxicated through intentional ingestion for recreational use.
• Routes for use: inhalation, ingestion, topical
• THC mimics endogenous cannabinoids and binds to cannabinoid receptors found throughout the nervous system, including in the amygdala, hippocampus, orbitofrontal cortex, hypothalamus, basal ganglia, cerebellum, and brain stem.
  • The effects of THC are exerted through the endocannabinoid system, which plays a role in regulating nervous system function and the brain’s reward system.
  • Receptors are also found within the lungs, liver, kidney, and hematopoietic cells.
• The pharmacodynamics of THC vary by route of use, with higher concentrations of THC exerting stronger effects.
  • Inhaled: Onset of psychoactive effects occurs rapidly, peaking at 15 to 30 minutes and lasting up to 4 hours.
  • Ingested: Onset of psychoactive effects is delayed up to 30 minutes to 3 hours and lasting up to 12 hours.
• THC is lipid-soluble and extensively binds adipose tissue.
  • THC remains in the body for extended periods due to its lipophilic properties, allowing it to accumulate and slowly release from fat cells.
• Metabolized by the liver
• Metabolites excreted through stool (65%) and urine (35%)