0071643192.pdf

TOXICOLOGY

TREATMENT

■ Supportive care

■ Passive and active cooling measures, as needed

■ Intravenous hydration

■ Muscle paralysis may be necessary for heat control.

■ Benzodiazepines: For sedation, hyperthermia, tachycardia, seizures, mus-

cular rigidity

■ Sodium bicarbonate: For wide complex dysrhythmias

■ Cocaine chest pain

■ Benzodiazepines

■ Aspirin

■ Nitroglycerin (phentolamine if no response)

■ Avoid

■ β-Blockers due to concern for unopposed α-receptor stimulation

COMPLICATIONS

■ Numerous, including dysrhythmias, MI, ischemic bowel, CNS bleed,

rabdoymyolysis, and IDU-related complications

Amphetamines

This is a large class of structurally related drugs. Medical indications include

attention deficit hyperactivity disorder, narcolepsy, and weight loss.

SPECIFICPREPARATIONS

■ Methamphetamine (“crank, ice”) synthesized from ephedrine; readily

absorbed from oral, parenteral, and inhalational routes

■ 3,4 methylenedioxymethamphetamine (MDMA, “ectasy, E”)

■ Ephedrine/ma-huang found in over the counter preparations, Chinese

herbal preparations, and legal stimulants; less potent than other ampheta-

mines alone

MECHANISM/TOXICITY

■ ↑Release of neurotransmitters (primarily norepinepherine and dopamine)

from presynaptic nerve terminals.

■ 5-HT 2 agonism and D 2 antagonism →hallucinations.

SYMPTOMS/EXAM

■ Similar to cocaine, but duration of action is considerably longer and may

last >24 hours

■ Na+channel blockade does notoccur.

DIAGNOSIS

■ Usually clear from history and exam

■ Urine screens are available in most hospitals

■ The results may be positive 2–3 days beyond period of toxicity.

■ Many drugs may cross react.

TREATMENT

■ As with cocaine toxicity above

Wide complex dysrhythmia

during cocaine intoxication is

due to sodium-channel

blockade and should be

treated with sodium

bicarbonate.

Specific anticonvulsant

medications, such as

phenytoin, are not indicated

for toxicologic seizures.