Acute, chronic, and withdrawal effects of illicit substances

The following is adapted from the National Institute on Drug Abuse (NIDA) publication Commonly Used Drugs.
  • Cannabinoids (marijuana, hashish)
    • acute effects: euphoria, slowed thinking and reaction time, confusion, impaired balance and coordination
    • chronic effects: cough, frequent respiratory infections, impaired memory and learning, increased heart rate, anxiety, panic attacks, tolerance, and addiction
    • withdrawal: insomnia, hyperactivity
  • Depressants (barbiturates, benzodiazepines, gamma-hydroxybutyrate (GHB), methaqualone)
    • acute effects (general): drowsiness, reduced anxiety, feeling or well-being with lowered inhibitions, slowed pulse and breathing, hypotension, poor concentration
      • Methaqualone is associated with euphoria/depression, hyporeflexia, slurred speech and coma.
      • GHB is also associated with nausea/vomiting, headache, loss of consciousness, loss of reflexes, seizures, coma, death.
      • Flunitrazepam (Rohypnol) is a benzodiazepine with the additional effects of visual and gastrointestinal disturbances, urinary retention, memory loss for the time under the drug's effects.
    • chronic effects: fatigue, confusion, impaired coordination, memory, and judgment; addiction, respiratory depression and arrest
    • withdrawal: anxiety, insomnia, tremors, seizures, death
  • Hallucinogens (lysergic acid diethylamide, mescaline, psilocybin):
    • acute effects (general): altered states of perception and feeling; nausea
      • LSD and mescaline cause hyperthermia, tachycardia, hypertension, loss of appetite, insomnia, numbness, weakness, and tremors.
      • Psilocybin is associated with nervousness and paranoia.
    • chronic effects: persisting perception disorder (flashbacks); LSD use may also lead to other persistent mental disorders
    • withdrawal: symptoms not reported
  • Opioids and morphine derivatives (codeine, fentanyl, heroin, morphine, opium, oxycodone, hydrocodone):
    • acute effects: pain relief, euphoria, drowsiness. Heroin use is associated with a staggering gait.
    • chronic effects: nausea, constipation, confusion, sedation, respiratory depression and arrest, tolerance, addiction, unconsciousness, coma, and death
    • withdrawal: flu-like symptoms, watery eyes, tremors, chills, diaphoresis
  • Stimulants (amphetamine, methamphetamine, cocaine,MDMA, nicotine)
    • acute effects (general): tachycardia, hypertension, increased metabolism, feelings of exhilaration,energy, and increased mental alertness
      • amphetamine: tachypnea
      • cocaine: hyperthermia
      • MDMA: hallucinogenic effect with increased tactile sensitivity and empathetic feelings
      • methamphetamine: aggression, violence, psychotic behavior
    • chronic use (general): rapid or irregular heart beat; reduced appetite, weight loss, heart failure, nervousness, insomnia
      • amphetamine: tremor, loss of coordination; irritability, anxiousness, restlessness, delirium, panic, paranoia, impulsive behavior, aggressiveness, tolerance, addiction, psychosis
      • cocaine: chest pain, respiratory failure, nausea, abdominal pain, strokes, seizures, headaches, malnutrition, panic attacks
      • MDMA: impaired memory and learning, hyperthermia, cardiac toxicity, renal failure, liver toxicity
      • methamphetamine: memory loss, cardiac and neurological damage; impaired memory and learning, tolerance, addiction
      • nicotine: additional effects attributable to tobacco exposure; adverse pregnancy outcomes; chronic lung disease, cardiovascular disease, stroke, cancer, tolerance, addiction
      • withdrawal: apathy, somnolence, irritability, depression, sinus congestion
  • Dissociative anaesthetics (ketamine, phencyclidine (PCP)
    • acute effects (general): increased heart rate and blood pressure, impaired motor function
      • ketamine: delirium, depression, respiratory depression and arrest at high doses
      • phencyclidine: hypotension and bradycardia, panic, aggression, violence/loss of appetite, depression
    • chronic effects: memory loss; numbness; nausea/vomiting
    • withdrawal: diarrhea, chills, tremor
  • Inhalants (solvents, gases, nitrites)
    • acute effects: stimulation, loss of inhibition, headache, nausea or vomiting, slurred speech, loss of motor coordination, wheezing, unconsciousness
    • chronic effects: abdominal pain, weight loss, muscle weakness, depression, memory impairment, damage of cardiovascular and nervous systems, sudden death
    • withdrawal: irritability, dysphoria, sleep disturbance, headache, dry mouth, lacrimation
Steroids (Anabolic)
  • acute toxic effects: none
  • chronic effects: hypertension, thrombosis, hyperlipidemia, hepatic dysfunction, liver and kidney cancer, hostility and aggression, acne. In adolescents, premature closure of growth plates. In males, prostate cancer, reduced sperm production, testicular atrophy, gynecomastia. In females, menstrual irregularities, development of facial hair and other masculine characteristics
  • withdrawal: adrenal insufficiency

Authors & Reviewers

Initial publication: May 2010; last update/revision: May 2011
Current Authors and Reviewers:
Reviewers: Scott Whittle, MD
Mark Pepper, MS, CPCI