Neuroleptic malignant syndrome

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Neuroleptic malignant syndrome
Synonyms	N/A
Pronounce	N/A
Specialty	N/A
Symptoms	Fever, muscle rigidity, autonomic dysfunction, altered mental status
Complications	Rhabdomyolysis, renal failure, seizures
Onset	Hours to days after starting or increasing antipsychotic medication
Duration	Days to weeks
Types	N/A
Causes	Antipsychotic medications, dopamine antagonists
Risks	High doses of antipsychotics, rapid dose escalation, dehydration, agitation
Diagnosis	Clinical evaluation, exclusion of other conditions
Differential diagnosis	Serotonin syndrome, malignant hyperthermia, encephalitis, heat stroke
Prevention	N/A
Treatment	Discontinuation of causative agent, supportive care, dantrolene, bromocriptine, benzodiazepines
Medication	N/A
Prognosis	Variable; can be life-threatening if untreated
Frequency	Rare
Deaths	N/A

Definition

Neuroleptic malignant syndrome is a rare neurological condition that is caused by an adverse reaction to neuroleptic (tranquilizer) or antipsychotic drugs. These drugs are commonly prescribed for the treatment of schizophrenia and other neurological, mental, or emotional disorders. The syndrome can also occur in people taking anti-Parkinsonism drugs known as dopaminergics if those drugs are discontinued abruptly.

Cause

The exact underlying cause of neuroleptic malignant syndrome is unknown. In some cases, more than one family member can be affected which suggests there may be a genetic component.

Onset

In most cases, the disorder develops within the first 2 weeks of treatment with the drug; however, the disorder may develop any time during the therapy period.

Signs and symptoms

Symptoms include high fever, sweating, unstable blood pressure, stupor, muscular rigidity, and autonomic dysfunction.

Clinical presentation

For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. 80%-99% of people have these symptoms

• Abnormal autonomic nervous system physiology
• Extrapyramidal muscular rigidity
• Fever
• Hyperhidrosis(Excessive sweating)
• Mutism(Inability to speak)

30%-79% of people have these symptoms

• Drooling(Dribbling)
• Dysphagia(Poor swallowing)
• Elevated serum creatine kinase(Elevated blood creatine phosphokinase)
• Fatigue(Tired)
• Leukocytosis(Elevated white blood count)
• Metabolic acidosis
• Muscle spasm
• Tachycardia(Fast heart rate)
• Tremor

5%-29% of people have these symptoms

• Acute kidney injury
• Agitation
• Anxiety(Excessive, persistent worry and fear)
• Aspiration pneumonia
• Chorea
• Coma
• Dehydration
• Delirium
• Elevated [[alkaline phosphatase](Greatly elevated alkaline phosphatase)
• Elevated hepatic transaminase(High liver enzymes)
• Encephalopathy
• Hyperkalemia(Elevated serum potassium levels)
• Hypernatremia(High blood sodium levels)
• Hyperphosphatemia(High blood phosphate levels)
• Hypertensive crisis
• Hyperuricemia(High blood uric acid level)
• Hypocalcemia(Low blood calcium levels)
• Hypomagnesemia(Low blood magnesium levels)
• Hyponatremia(Low blood sodium levels)
• Hypotension(Low blood pressure)
• Increased lactate dehydrogenase level
• Myoglobinuria
• Nasogastric tube feeding
• Nausea
• Oculogyric crisis
• Proteinuria(High urine protein levels)
• Pulmonary embolism(Blood clot in artery of lung)
• Rhabdomyolysis(Breakdown of skeletal muscle)
• Rigors
• Thrombocytosis(Increased number of platelets in blood)
• Urinary incontinence(Loss of bladder control)
• Vomiting(Throwing up)

Diagnosis

• The diagnosis of NMS is based on history and the presence of certain physical examination and laboratory findings..
• Patients typically develop NMS within hours or days after exposure to a causative drug, with most exhibiting symptoms within 2 weeks and nearly all within 30 days.
• NMS has classically been characterized by the presence of the triad of fever, muscle rigidity, and altered mental status.

Treatment

• Generally, intensive care is needed.
• The neuroleptic or antipsychotic drug is discontinued, and the fever is treated aggressively.
• A muscle relaxant may be prescribed.
• Dopaminergic drugs, such as a dopamine agonist, have been reported to be useful.

Prognosis

• Early identification of and treatment for individuals with neuroleptic malignant syndrome improves outcome.
• If clinically indicated, a low potency neuroleptic can be reintroduced very slowly when the individual recovers, although there is a risk that the syndrome might recur.
• Another alternative is to substitute another class of drugs for the neuroleptic.
• Anesthesia may be a risk to individuals who have experienced neuroleptic malignant syndrome.

NIH genetic and rare disease info

• NIH info on Neuroleptic malignant syndrome

Neuroleptic malignant syndrome is a rare disease.