Sympathomimetic Poisoning

Description

• Direct or indirect stimulation of adrenergic receptors in sympathetic and central nervous systems
• Often no correlation between dosage and degree of toxicity
• Cocaine may also block sodium channels of cardiac myocytes, leading to “tricyclic” or class 1a–type dysrhythmias

• Sympathomimetic poisoning in children may present similarly to meningitis or other systemic illness
• Urinary toxicology screening may have a role in discovering sympathomimetic poisoning in children presenting with altered mental status
• Methylphenidate (Ritalin, Concerta), lisdexamfetamine (Vyvanse), and other sympathomimetics used for ADHD may cross-react with altered mental status

Etiology

• Sympathomimetic toxicity can result from use of any sympathetically active drug, including:
  • All amphetamines, methamphetamines, and derivatives (ecstasy, MDMA, Molly)
  • Cocaine (including “Speed Ball”) when opioid reversed with naloxone
  • Synthetic cathinones “Bath Salts”
  • Phencyclidine (PCP)
  • Lysergic acid diethylamide (LSD)
  • Decongestants (rare)
• Drug delivery routes: Inhalation, injection, snorting, or ingestion