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TOXICOLOGY

Selegiline

■ Limited data, may see classic MAOI toxicity

DIAGNOSIS

■ Clinical diagnosis is based on history and examination.

■ Selegiline is metabolized to L-methamphetamine, which can be detected

on urine toxicology screening.

TREATMENT

■ Supportive care

■ Cessation of medication

■ Sedation with benzodiazepines, as needed

ANTIPSYCHOTICS

Antipsychotics were developed for the treatment of psychoses, but are also

commonly used in the treatment of N/V, migraines, and to control the agitated

patient.

Therapeutic effects are due to antagonism of mesolimbic dopamine recep-

tors, but variable affinity for other receptors causes a variety of side effects and

toxicity in therapeutic use.

They are divided into two major groups (see Table 6.11):

Typical antipsychotics

■ The original medications introduced in the 1950s

■ Characterized by less receptor specificity → greater incidence of side

effects than newer agents

Atypical antipsychotics

■ The newer generation medications, first introduced in the 1990s

Acute overdose is common, but toxicity resulting in severe morbidity or mor-

tality is rare.

MECHANISM/TOXICITY

■ Nonspecific dopamine receptor antagonism →extrapyramidal symptoms

and neuroleptic malignant syndrome.

■ α 1 -Adrenergic antagonism →orthostatic hypotension and reflex tachycardia.

TABLE 6.11. Common Antipsychotic Agents

TYPICALANTIPSYCHOTICS ATYPICALANTIPSYCHOTICS

Haloperidol (Haldol) Risperidone (Risperdal)

Chlorpromazine (Thorazine) Quitiapine (Seroquel)

Promethazine (Phenergan) Olanzapine (Zyprexa)

Proclorperazine (Compazine) Aripiprazole (Abilify)