Kaplan + Sadock's Synopsis of Psychiatry, 11e

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Chapter 29: Psychopharmacological Treatment

Medication-Induced Postural Tremor Diagnosis, Signs, and Symptoms Tremor is a rhythmic alteration in movement that is usually faster than one beat per second. Fine tremor (8 to 12 Hz) is most common. Epidemiology Typically, tremors decrease during periods of relaxation and sleep and increase with stress or anxiety. Etiology Whereas all the above diagnoses specifically include an associa- tion with a neuroleptic, a range of psychiatric medications can produce tremor—most notably, lithium, stimulants, antidepres- sants, caffeine, and valproate (Depakene). Table 29.2-5 Drug-Induced Central Hyperthermic Syndromes a

Treatment The treatment involves four principles: 1. The lowest possible dose of the psychiatric drug should be taken. 2. Patients should minimize caffeine consumption. 3. The psychiatric drug should be taken at bedtime to minimize the amount of daytime tremor. 4. b -adrenergic receptor antagonists (e.g., propranolol [Inderal]) can be given to treat drug-induced tremors.

Other Medication-Induced Movement Disorders Nocturnal Myoclonus

Nocturnal myoclonus consists of highly stereotyped, abrupt contractions of certain leg muscles during sleep. Patients lack any subjective awareness of the leg jerks. The condition may

Condition (and Mechanism)

Possible Treatment b

Common Drug Causes Frequent Symptoms

Clinical Course

Hyperthermia

Atropine, lidocaine, meperidine NSAID toxicity,

Hyperthermia, diaphoresis, malaise

Acetaminophen per

Benign, febrile seizures in children

( ↓ heat dissipation) ( ↑ heat production)

rectum (325 mg every 4 hrs), diazepam oral or per rectum (5 mg every 8 hrs) for febrile seizures

pheochromocytoma, thyrotoxicosis

Malignant hyperthermia ( ↑ heat production)

NMJ blockers

Hyperthermia muscle rigidity, arrhythmias, ischemia, c hypotension, rhabdomyolysis; disseminated intravascular coagulation Hyperthermia, confusion, visual hallucinations, agitation, hyperreflexia, muscle relaxation, anticholinergic effects (dry skin, pupil dilation), arrhythmias Hyperthermia excitement, hyperreflexia

Dantrolene sodium (1–2 mg/kg/min IV infusion) d

Familial, 10% mortality if untreated

(succinylcholine), halothane

Tricyclic overdose

Tricyclic

Sodium bicarbonate

Fatalities have occurred if untreated

( ↑ heat production)

antidepressants, cocaine

(1 mEq/kg IV bolus) if arrhythmia is present, physostigmine (1–3 mg IV) with cardiac monitoring

Autonomic hyperreflexia ( ↑ heat production)

CNS stimulants

Trimethaphan (0.3–7 mg/ min IV infusion)

Reversible

(amphetamines)

Lethal catatonia

Lead poisoning

Hyperthermia, intense anxiety, destructive behavior, psychosis

Lorazepam (1–2 mg IV every 4 hrs),

High mortality if untreated

( ↓ heat dissipation)

antipsychotics may be contraindicated Bromocriptine (2–10 mg every 8 hrs orally or nasogastric tube), lysuride (0.02– 0.1 mg/hr IV infusion), carbidopa-levodopa (Sinemet) (25/100 PO every 8 hrs), dantrolene sodium (0.3–1 mg/kg IV every 6 hrs)

Neuroleptic malignant syndrome (mixed; hypothalamic, ↓ heat dissipation, ↑ heat production)

Antipsychotics

Hyperthermia, muscle rigidity, diaphoresis (60%), leukocytosis, delirium, rhabdomyolysis, elevated CPK, autonomic deregulation, extrapyramidal symptoms

Rapid onset,

(neuroleptics), methyldopa, reserpine

20% mortality if untreated

NSAID, nonsteroidal anti-inflammatory drug; MAOI, monoamine oxidase inhibitor; NMJ, neuromuscular junction; CNS, central nervous system; CPK, creatine phosphokinase; PO, orally; IV, intravenously. a Boldface indicates features that may be used to distinguish one syndrome from another. b Gastric lavage and supportive measures, including cooling, are required in most cases. c Oxygen consumption increases by 7% for every 1 ° F increase in body temperature. d Has been associated with idiosyncratic hepatocellular injury, as well as severe hypotension in one case. (From Theoharides TC, Harris RS, Weckstein D. Neuroleptic malignant-like syndrome due to cyclobenzaprine? [letter]. J Clin Psychopharmacol 1995;15:80, with permission.)