Evaluating sympathomimetic intoxication in an emergency setting

Sympathomimetic-like drugs (ie, cocaine, amphetamines and sympathomimetic a mines) mimic the actions of the endogenous neurotransmitters that stimulate the sympathetic nervous system. The classic signs and symptoms (toxidrome) often seen with the sympathomimetic drugs include hyperactivity, mydriasis (dilated pupils), hypertension, tachycardia, and hyperthermia; some of the se drugs also precipitate psychoses hallucinations and seizures. Qualitativ e confirmation by the laboratory that the patient is experiencing a sympath omimetic drug reaction can be helpful to the clinician. However, some of th e conventional toxicologic drug screens used by many clinical laboratories do not differentiate within a specific class of drugs (eg, amphetamine vs m ethamphetamine). Although a drug screen can help to confirm ingestion of a sympathomimetic drug, diagnosis and treatment are often bared on history of use (often unreliable), physical examination, and the classic toxidrome ob served with this class of drugs.