Poisoning and Overdose Answers 255diarrhea. It is difficult to distinguish from cocaine overdose and diagnosis
relies on the medication history.
227.The answer is d.(Rosen, pp 2066-2067.)A major change has occurred
in the approach of GI decontamination over the past decade. Previous rec-
ommendations indicated that the stomach should be emptied by either syrup
of ipecac or by gastric lavage. Activated charcoal alone has demonstrated
similar or superior results and now is the recommended GI decontaminant.
The complications of gastric emptying procedures, primarily aspiration, are
largely avoided when only activated charcoal is used. Most ingested drugs
and chemicals are adsorbed to activated charcoal. The few agents that do not
adsorb to charcoal include ions(eg, mineral acids and alkalis, lithium,
borates, bromides), hydrocarbons (HCs), metals(eg, iron), and ethanol.
The patient in question ingested lithiumthat is used to treat her bipolar
disorder. A lithium level should be drawn and management decided based on
those results. Potential treatments include whole-bowel irrigation and dialysis.
The substances in the other answer choices are absorbed by activated
charcoal.
228.The answer is e.(Goldfrank et al, pp 1004-1014. Rosen, pp 2119-
2124.)Benzodiazepines (eg, diazepam)should be used as the first-line
agent for nearly all cocaine toxicities. Many effects of cocaine are thought to
be mediated through CNS stimulation by the release or inhibiting the reup-
take of catecholamines. The effects that acute cocaine intoxication has on
the heart include coronary vasoconstriction with increasing myocardial
oxygen demand. The goal of lowering the BP in this patient is to reverse the
vasoconstriction by norepinephrine at peripheral α-adrenergic receptors.
Benzodiazepines restore the CNS inhibitory tone on the peripheral nervous
system. The use of β-adrenergic antagonists should be avoided with cocaine
because of paradoxical hypertension and coronary artery vasoconstriction
because of unopposed α-adrenergic receptor stimulation.
(a)Although haloperidol can be used for sedation, its anticholinergic
effects can limit cooling by impeding diaphoresis and may increase mor-
bidity. (b and c) It is best to avoid β-adrenergic antagonists in the setting of
cocaine intoxication. Their use leads to unopposed α-adrenergic stimula-
tion that results in vasoconstrictionand hypertension. Although labetalol is
anα- and β-adrenergic receptor blocker, it has substantially more β-adrenergic
antagonism than α-adrenergic antagonist effects. (d)The data regarding the
efficacy of calcium channel blockers (CCBs) for the treatment of cocaine