Amphetamine & Cocaine Overdose

KEY FEATURES

• Amphetamines and cocaine are widely used for their euphorigenic and stimulant properties

• Both drugs may be smoked, snorted, ingested, or injected

• The toxic dose of each drug is highly variable and depends on the route of administration and individual tolerance

• The onset of effects is most rapid after intravenous injection or smoking

• Amphetamine derivatives and related drugs include

  • Methamphetamine ("crystal meth," "crank")

  • MDMA (3,4-Methyl​enedioxy​methamphetamine [“ecstasy”])

  • Ephedrine

  • Methcathinone ("cat" or "khat")

  • Methcathinone derivatives and related synthetic chemicals (eg, methylenedioxypyrovalerone [MDPV] is often sold as purported "bath salts")

  • Amphetamine-like reactions have also been reported after use of synthetic cannabinoids (eg, "Spice" and "K2")

• Amphetamines and cocaine may be adulterated with fentanyl or fentanyl analogs resulting in

  • Unexpected coma

  • Respiratory depression

  • Death

• Nonprescription medications and nutritional supplements may contain stimulant or sympathomimetic drugs, such as

  • Ephedrine

  • Yohimbine

  • Caffeine

CLINICAL FINDINGS

Symptoms and Signs

• Anxiety

• Tremulousness

• Tachycardia

• Hypertension

• Diaphoresis

• Dilated pupils

• Agitation

• Muscular hyperactivity (may lead to metabolic acidosis and rhabdomyolysis)

• Psychosis

• In severe intoxication, seizures and hyperthermia may occur

• Sustained or severe hypertension may result in intracranial hemorrhage, aortic dissection, or myocardial infarction

• Chronic use may cause cardiomyopathy

• Ischemic colitis has been reported

• Hyponatremia has been reported after MDMA use

DIAGNOSIS

Laboratory Tests

• Urine screening usually tests for amphetamines, cocaine metabolite benzoylecgonine

• Blood screening is generally not sensitive enough to detect these drugs

TREATMENT

• Emergency and supportive measures

  • Maintain patent airway and assist ventilation, if necessary

  • Rapidly lower the body temperature (see Hyperthermia) in patients who are hyperthermic (39–40°C)

  • Give intravenous fluids to prevent myoglobinuric kidney injury in patients who have rhabdomyolysis

• Medications

  • Treat agitation, psychosis, or seizures with a sedating benzodiazepine such as diazepam, 5–10 mg, or lorazepam, 2–3 mg intravenously

  • Add phenobarbital (15 mg/kg intravenously) for persistent seizures

  • Treat hypertension with a vasodilator drug, such as phentolamine (1–5 mg intravenously), or nitroprusside, or a combined α- and beta-adrenergic blocker (such as labetalol, 10–20 mg intravenously)

  • Do not administer a pure beta-blocker, such as propranolol alone, because this may result in paradoxical worsening of the hypertension as a result of unopposed alpha-adrenergic effects

  • Treat tachycardia or tachyarrhythmias with a short-acting beta-blocker such as esmolol, 25–100 mcg/kg/min by intravenous infusion

• Treat hyponatremia (see Hyponatremia)

• Treat hyperthermia (see Hyperthermia)