0071643192.pdf

TOXICOLOGY

SYMPTOMS/EXAM

■ Behavioral changes (eg, increased sociability, irritability, aggressiveness,
etc.)
■ CNS depression ranging from mild sedation to coma
■ Ataxia, gait instability

DIFFERENTIAL

■ Consider other etiologies of CNS depression, especially with relatively low
serum ethanol levels.
■ Common conditions associated with ethanol use include hypoglycemia,
withdrawal, head trauma, and other toxin/drug overdose.

TABLE 6.4. ECG Findings and Associated Classes of Drugs

Bradysrhythmias β-Blockers

Sinus bradycardia Ca++channel blockers

AV block Cardiac glycosides

Clonidine

Other antidysrhythmic agents

Tachydysrhythmias Anticholinergics

Sinus tachycardia Sympathomimetics

SVT Stimulants

Ventricular tachycardia (VT)

QRS widening Na++channel blocking drugs:

Some anticholinergics

Tricyclic antidepressants

Sympathomimetics

QTc prolongation Antidysrhythmic agents

Screening tool for conduction Antipsychotic medications

abnormality that could degenerate Antidepressants

into torsades de points Many others

Ischemic changes Sympathomimetics

Stimulants

Classic toxicology-related ECG findings Digoxin

Digitalis effect—seen in both therapeutic

use and overdose

Digoxin-induced bidirectional VT (rare)

Tricyclic antidepressants

Rightward deviation of the terminal

40 msec of the QRS axis