Neuroleptic malignant syndrome is a pathology characterized by a disease at the neurological level. This syndrome is generally the result of side effects when taking drugs such as neuroleptics or anti-psychotics. (2)

This syndrome is linked to the idiosyncratic state, that is to say the way of being of each individual, his reactions and his behavior with his environment.

This pathology leads to high fevers, sweating, instability in terms of blood pressure, muscle rigidity and dysfunctions in the automatisms.

In the majority of cases, the first symptoms appear after two weeks of treatment with neuroleptics or anti-psychotics. However, symptoms associated with the disease may appear throughout the period of taking the medication.

Cases of neuroleptic malignant syndrome have also been brought to the fore following discontinuous treatment with anti-Parkinson drugs. (2)

The rapid diagnosis of neuroleptic malignant syndrome caused by taking neuroleptics or anti-psychotics makes it possible to reduce the associated consequences.

Neuroleptic malignant syndrome affects approximately 1 to 2 cases in 10 patients undergoing neuroleptic or antipsychotic treatment. This prevalence concerns both men and women with a slight predominance for men, of all ages. (000)

Neuroleptic malignant syndrome is associated with various clinical features such as: (1)

• pyrexia: presence of an intense fever or a permanent febrile state;
• muscle hypertonia: increased tone in the muscles;
• changes in mental states;
• haemodynamic deregulation (deregulation in the blood circulation)

A characteristic specific to neuroleptic malignant syndrome is the presence of significant muscular rigidity associated with an absence of reflexes: “lead-pipe” rigidity. (1)

Characteristics in terms of vital signs are also observable in this type of pathology: (4)

• hypertension;
• tachycardia (rapid heartbeat);
• tachypnea (rapid breathing);
• hyperthermia (> 40 °), caused by the presence of an intense fever;
• hypersalivation;
• acidosis (acidification of the blood with a blood pH lower than its normal level which is between 7.38 and 7.42.);
• incontinence.

Changes in biological parameters are also visible in this type of disease: (4)

• a higher level of serum phosphokinases and transaminases;
• rhabdomyolysis (destruction of muscle tissue within striated muscles).

The development of neuroleptic malignant syndrome arises from side effects associated with taking drugs of the types: neuroleptics and anti-psychotics.

The most important risk factor in the development of neuroleptic malignant syndrome is the use of neuroleptics or anti-psychotics. (4)

In addition, physical exhaustion, restlessness, dehydration are additional factors in terms of the risk of developing the disease.

Patients taking neuroleptics or anti-psychotics at high doses, in the parenteral form (administration of the drug by the intravenous, intramuscular route, etc.) or with a rapid increase in the dosage have a greater risk of developing the pathology. (4)

Treatment for this syndrome is usually intensive.

The drug causing the illness (neuroleptic or antipsychotic) is stopped and the fever is treated intensively.

Medicines allowing muscle relaxation may be prescribed. In addition, dopamine-based treatments (dopaminergic drugs) are often useful in the treatment of this pathology. (2)

To date, no specific treatment for this syndrome has been the subject of concrete evidence.

Nevertheless, the benefits of treatment with benzodiazepines, dopaminergic agents (bromocriptine, amantadine), dantrolenes (muscle relaxants) and electroconvulsive therapy have been reported.

Careful monitoring is necessary in patients with cardio-respiratory failure, renal failure, aspiration pneumonia and coagulopathy.

In addition, respiratory assistance and dialysis may be prescribed.

In most cases, patients with neuroleptic malignant syndrome make a full recovery. However, amnesic symptoms, extrapyramidal (together with neurological disorders), brain disorders, peripheral neuropathy, myopathy and contractures may persist in some cases. (4)

In the absence of treatment and after stopping the psychotropic drug that causes the disease, neuroleptic malignant syndrome is generally cured between 1 and 2 weeks.

In addition, the syndrome is potentially fatal.

The causes of death in the context of this disease are cardiopulmonary arrest, aspiration pneumonia (pulmonary involvement characterized by reflux of fluid into the bronchi from the stomach), pulmonary embolism, myoglobinuric renal failure (renal failure with the presence of blood in the urine), or disseminated intravascular coagulation. (4)

The mortality rate associated with this pathology is between 20 and 30%.