Heroin Intoxication



Heroin is a semisynthetic derivative of opium. The opioid family includes the following:

  • Drugs that occur naturally in opium (from the poppy plant)
  • Codeine
  • Morphine
  • Semisynthetic derivatives (e.g., hydromorphone, oxycodone)
  • Synthetic compounds (e.g., meperidine, fentanyl, methadone)


  • General
    • 23 years of age: mean age of 1st use (2012)
    • ~50% of those who have used an opioid pain reliever for nonmedical uses state they obtained it for free from a friend or relative.
    • Nonmedical use of opioid pain relievers can lead to eventual injection heroin use.
  • Neonatal
    • Fetal exposure commonly involves polysubstance abuse.
    • 60–80% of heroin-exposed infants develop withdrawal—dependent on maternal dosing and length of use.
  • Adolescents
    • Most use experimentally or intermittently; few become addicted and use daily.
    • Use of opioid analgesics has increased dramatically over the last 10 years and has become more common than heroin use.
    • Most common substances were oxycodone, hydrocodone, and methadone
  • Overdose
    • Up to 1/3 of heroin users experience nonfatal overdose.
    • Most occur in the home and with other people present.
    • Risk factors include length of injecting history, concurrent use of CNS depressants, recent completion of substance abuse program, and recent release from prison.
  • Deaths
    • Most heroin deaths occur when drug is administered IV.
    • Most deaths in patients in their late 20s or 30s, with significant drug dependence
    • Males are 4 times more likely to die than females from heroin-related causes.
    • Multiple drug use common in heroin-related death
    • As of 2011, opioid pain relievers are responsible for more overdose fatalities than heroin and cocaine combined.


  • Precise estimates of prevalence of use difficult
  • ~2.9 million people used at least once.
  • ~467,000 used in 2012 (double since 2001).
  • Prevalence of fetal exposure <1–3.7%


  • Well-absorbed from gastrointestinal (GI) tract, nasal mucosa, pulmonary capillaries, and SC and IM injection sites
  • Oral dose less potent than parenteral because of 1st-pass hepatic metabolism
  • IV heroin peaks in <1 minute; intranasal and IM heroin peak in 3–5 minutes.
  • Very lipid soluble; crosses blood–brain barrier within 15–20 seconds
  • Extensive distribution into skeletal muscle, kidneys, liver, intestine, lungs, spleen, brain, and placenta
  • Rapidly crosses the placenta, entering fetal tissues within 1 hour
  • Crosses into breast milk in quantities sufficient to cause addiction
  • Excreted in urine as morphine
  • Receptor types
    • Mu (or OP3)
      • Located in CNS, GI tract, and sensory nerve endings
      • Effect: analgesia, euphoria, respiratory depression, physical dependence, GI dysmotility, miosis, pruritus, bradycardia
      • Kappa (or OP2)
      • Located in CNS
      • Effect: analgesia, miosis, diuresis, dysphoria
      • Delta (or OP1)
      • Located in CNS
      • Effect: spinal analgesia, modulation of mu receptors/dopaminergic neurons

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