0071643192.pdf

PSYCHOBEHAVIORAL DISORDERS

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EPHEDRINE

■ Has both α-andβ-adrenergic activitycaused by release of dopamine and

NE from neuronal stores

■ Widely available in health food stores

■ Can cause severe cardiovascular and neurologic toxicity, psychosis, hyper-

tension if abused

PHENYLPROPANOLAMINE

■ Aperipheralα-adrenergic agonistthat causes significant vasoconstriction

with hypertension and reflex bradycardia

■ Has been withdrawn from the marketsecondary to associated intracranial

hemorrhage

Opioids

Opiatesproperly refer to products derived from opium alkaloids (eg, mor-

phine, codeine) and nonalkaloids (eg, heroin). Opioidsare any drug that has

morphine-like effects by binding to the opioid receptors in the CNS (eg,

propoxyphene, methadone).

SYMPTOMS/EXAM

Symptoms vary with dose and frequency of use. Patients typically present with

psychomotor agitation or retardation, impaired judgment and attention, drowsi-

ness or coma, slurred speech, respiratory depression.

DIFFERENTIAL

Alcohol intoxication, sedative/hypnotic use, toxic overdose (clonidine, organo-

phosphates, phenothiazines), carbon monoxide poisoning, hypoglycemia,

hypoxia, CNS infections, postictal states, pontine hemorrhage

DIAGNOSIS

Diagnosis is clinical. Classic triad is coma, miosis, and respiratory depression.

TREATMENT

■ ABCs, IV/O 2 /monitor, dextrose stick

■ Narcan is a pure antagonist that can be administered via IV, IM, SC, SL,

or via the endotracheal tube. It is effective in life-threatening overdoses or

if the diagnosis is uncertain.

■ Onset of action is 1–2 minutes.

■ Duration is about 20–60 minutes. Repeated boluses or an infusion may

be necessary, especially for long-acting opioids such as methadone.

■ Begin with small doses 0.2–0.4 mg to avoid acute withdrawal.

■ Observe for 4–6 hours in the ED, and admit those with long-lasting inges-

tion, those requiring an infusion or repeated boluses.

ACUTELUNGTOXICITY

■ A rare complication of opioid toxicity

■ Suspect in any patient with tachypnea, rales, decreased O 2 saturations

with normal cardiac silhouette on CXR

Pupillary constriction is not

always present as patients can

get mydriasis from coingestants

or anoxia. Furthermore,

meperidine, propoxyphene,

and pentazocine may dilate the

pupils.

Remember to check an

acetaminophen level on

patients with possible

ingestion of an opioid-

acetaminophen combination.