Disease Information for Neuroleptic malignant syndrome: Definition

  • A potentially fatal syndrome associated primarily with the use of neuroleptic agents (see ANTIPSYCHOTIC AGENTS) which are in turn associated with dopaminergic receptor blockade in the BASAL GANGLIA and HYPOTHALAMUS, and sympathetic dysregulation; Clinical features include diffuse MUSCLE RIGIDITY; TREMOR; high FEVER; diaphoresis; labile blood pressure; cognitive dysfunction; and autonomic disturbances; Serum CPK level elevation and a leukocytosis may also be present; (From Adams et al, Principles of Neurology, 6th ed,).

    Neuroleptic Malignant Syndrome; Drug-Induced Movement Disorder; Hyperthermia; Neuroleptic-Induced Acute Dystonia; Neuroleptic malignant syndrome is a rare but potentially life-threatening reaction to the use of almost any of a group of antipsychotic drugs or major tranquilizers (neuroleptics); These drugs are commonly prescribed for the treatment of schizophrenia and other neurological, mental, or emotional disorders; Several of the more commonly prescribed neuroleptics include thioridazine, haloperidol, chlorpromazine, fluphenazine and perphenazine; The syndrome is characterized by high fever, stiffness of the muscles, altered mental status (paranoid behavior), and autonomic dysfunction; Autonomic dysfunction alludes to defective operations of the components of the involuntary (autonomic) nervous system, leading to wide swings of blood pressure, excessive sweating and excessive secretion of saliva; A genetic basis for the disorder is suspected but not proven; It does appear to be clear that a defect in the receptors to dopamine (dopamine D2 receptor antagonism) is an important contributor to the cause of neuroleptic malignant syndrome;

    -- NORD 2005 --

    Malignant hyperthermia syndrome is an adverse reaction to dopamine-blocking neuroleptics characterized by hyperthermia, muscular rigidity, autonomic dysfunction, and altered consciousness; Malignant hyperthermia;

    0.5% to 1% of patients receiving neuroleptics; More than two thirds of patients are male; Young and middle-aged adults; peak 42 yr; Malignant hyperthermia is the familial variant/disorder of neuroleptic syndrome; Differential DX: Heat stroke; Catatonia; Similar syndromes: possible complication of anesthesia, thyroid storm, toxins; Need a Careful drug history; Elevated CPK; Urinary myoglobin; Leukocytosis; Clinical: "Lead pipe" rigidity; Hyperthermia (38-6° to 42-3° C); Profuse sweating; Tachycardia;Labile BP; Semicomatose; ETIOLOGY: History of haloperidol use in 65% of cases; History of combination drug therapy in 34% of cases; Rare cases after withdrawal of dopamine agonists.