Substance Use Disorders



Any pattern of substance use causing significant physical, mental, or social dysfunction

  • Substances of abuse include:
    • Alcohol
    • Tobacco
    • Prescription medications
      • Opioids and morphine derivatives (buprenorphine, codeine, fentanyl, hydrocodone, hydromorphone, meperidine, methadone, morphine, oxycodone, oxymorphone)
      • CNS depressants (barbiturates, benzodiazepines, hypnotics)
      • Stimulants (amphetamines, methylphenidate)
      • Dextromethorphan (“Robo-tripping”)
    • Cannabis (marijuana, hashish, cannabis oil, and extracts); also sold as highly concentrated extracts (up to 90% THC) for use in vaporizers
    • Synthetic cannabinoids (Spice, K2, fake weed); often much more potent than marijuana; may be smoked, brewed in tea, or vaporized
    • Stimulants (cocaine, amphetamines, methamphetamines, Khat)
    • “Club drugs” (MDMA [ecstasy, Molly], PMMA [Superman], flunitrazepam, γ-hydroxybutyrate [GHB])
    • Opioids (heroin, opium, kratom, carfentanil, desomorphine [Krokodil], U-47700 [Pink])
    • Dissociative drugs (ketamine, phencyclidine [PCP], tenocyclidine [TCP])
    • Hallucinogens (lysergic acid diethylamide [LSD], salvia, ayahuasca, N,N-dimethyltryptamine [DMT])
    • Synthetic cathinones (bath salts, α-PVP [Flakka])
    • Inhalants (glue, paint thinners, nitrous oxide)
  • Synonym(s): drug abuse; drug dependence; substance abuse

Geriatric Considerations

  • Alcohol is the most commonly abused substance, and abuse often goes unrecognized.
  • Higher potential for drug interactions

Pregnancy Considerations
Substance abuse may cause fetal abnormalities, morbidity, and fetal or maternal death.

The prevalence of opioid use in pregnancy and associated neonatal abstinence syndrome have increased significantly in recent years. Screen for substance use at the first prenatal visit with a brief intervention and refer for treatment to improve maternal and neonatal outcomes (1)[C].



  • Predominant age: 18 to 25 years
  • Predominant sex: male > female


  • 57.2 million Americans (20.8%) reported illicit drug use in the past year in 2019.
  • 17.2% of 12- to 17-year-olds; 39.1% of 18- to 25-year-olds
  • 1 in 3 (35.4%) young adults were past year users of marijuana.
  • 70.6% of drug overdose deaths in 2019 were opioid related.

Etiology and Pathophysiology

Multifactorial, including genetic, environmental

Substances of abuse affect dopamine, acetylcholine, γ-aminobutyric acid, norepinephrine, opioid, and serotonin receptors. Variant alleles may account for differences in susceptibility to misuse of different substances.

Risk Factors

  • Male gender, young adult
  • Depression, anxiety
  • Family history
  • Peer or family use or approval; family dysfunction or trauma
  • Low socioeconomic status; unemployment
  • Accessibility of substances of abuse
  • Antisocial personality disorder
  • Academic problems, school dropout
  • Criminal involvement

General Prevention

  • Early identification and aggressive early intervention improve outcomes.
  • Universal school-based interventions are modestly effective for preventing drug use among adolescents.

Commonly Associated Conditions

  • Depression; bipolar affective disorder
  • Personality disorders
    Prescription narcotic overdose is the leading cause of accidental death in patients between the ages of 23 and 45 years in the United States.
  • Many states require naloxone to be prescribed or offered when issuing a prescription of opioids to patients at increased risk of overdose, such as those receiving ≥50 morphine milligram equivalents per day of an opioid, those taking both opioids and benzodiazepines, and those with a history of substance abuse.

There's more to see -- the rest of this topic is available only to subscribers.