Neuroleptic malignant syndrome

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Neuroleptic malignant syndrome
Haloperidol (Haldol).jpg
Haloperidol, a known cause of NMS
Specialty Critical care medicine, neurology, psychiatry
Symptoms High fever, confusion, rigid muscles, variable blood pressure, sweating [1]
Complications Rhabdomyolysis, high blood potassium, kidney failure, seizures [1] [2]
Usual onsetWithin a few weeks or days [3]
Causes Antipsychotic medication [1]
Risk factors Dehydration, agitation, catatonia [4]
Diagnostic method Based on symptoms in someone who has started on antipsychotics within the last month [2]
Differential diagnosis Heat stroke, malignant hyperthermia, serotonin syndrome, lethal catatonia [2]
TreatmentStopping the offending medication, rapid cooling, starting other medications [2]
Medication Dantrolene, bromocriptine, diazepam [2]
Prognosis 10–15% risk of death [4]
Frequency15 per 100,000 per year (on neuroleptics) [1]

Neuroleptic malignant syndrome (NMS) is a rare [5] [6] but life-threatening reaction that can occur in response to antipsychotics (neuroleptic) or other drugs that block the effects of dopamine. [1] [7] Symptoms include high fever, confusion, rigid muscles, variable blood pressure, sweating, and fast heart rate. [1] Complications may include muscle breakdown (rhabdomyolysis), high blood potassium, kidney failure, or seizures. [1] [2]

Contents

Any medications within the family of antipsychotics can cause the condition, though typical antipsychotics appear to have a higher risk than atypicals, [1] specifically first generation antipsychotics like haloperidol. [5] Onset is often within a few weeks of starting the medication but can occur at any time. [1] [3] Risk factors include dehydration, agitation, and catatonia. [4]

Rapidly decreasing the use of levodopa or other dopamine agonists, such as pramipexole, may also trigger the condition. [1] [8] The underlying mechanism involves blockage of dopamine receptors. [1] Diagnosis is based on symptoms. [2]

Management includes stopping the triggering medication, rapid cooling, and starting other medications. [2] Medications used include dantrolene, bromocriptine, and diazepam. [2] The risk of death among those affected is about 10%. [4] Rapid diagnosis and treatment is required to improve outcomes. [1] Many people can eventually be restarted on a lower dose of antipsychotic. [2] [3]

As of 2011, among those in psychiatric hospitals on antipsychotics about 15 per 100,000 are affected per year (0.015%). [1] In the second half of the 20th century rates were over 100 times higher at about 2% (2,000 per 100,000). [1] Males appear to be more often affected than females. [1] The condition was first described in 1956. [1]

Signs and symptoms

NMS symptoms include: [9]

The first symptoms of neuroleptic malignant syndrome are usually muscle cramps and tremors, fever, symptoms of autonomic nervous system instability such as unstable blood pressure, and sudden changes in mental status (agitation, delirium, or coma). Other possible symptoms include sweating, trouble swallowing, tremors, incontinence, and mutism. Once symptoms appear, they may progress rapidly and reach peak intensity in as little as three days. [9] These symptoms can last anywhere from eight hours to forty days, with the median duration of symptoms, with treatment, being nine days. [4] [7] The median onset of symptoms is four days after initiating the offending medication, but in some cases symptoms may begin up to 30 days later. [7]

Symptoms are sometimes misinterpreted by doctors as symptoms of mental illness which can result in delayed treatment. [11] Symptoms may also be mistaken for similarly presenting conditions such as malignant hyperthermia, serotonin syndrome, or withdrawal from illicit drugs such as alcohol cocaine, or MDMA. [7]

Neuroleptic malignant syndrome (NMS) usually presents with a "lead pipe rigidity" in which the muscles are stiffened and resistance is observed throughout the range of motion on testing. Severe cases may present as catatonia in which the person is not responsive to stimuli. [7]

The deep tendon reflexes in NMS are usually preserved whereas in serotonin syndrome presents with myoclonus or hyperactive muscle reflexes. [7]

Causes

NMS is usually caused by antipsychotic drug use, but other dopaminergic blocking drugs can also be a cause. [12] Individuals using butyrophenones (such as haloperidol and droperidol) or phenothiazines (such as promethazine and chlorpromazine) are reported to be at greatest risk. However, various atypical antipsychotics such as clozapine, olanzapine, risperidone, quetiapine, and ziprasidone have also been implicated in cases. [13]

NMS may also occur in people taking dopaminergic drugs (such as levodopa) for Parkinson's disease, most often when the drug dosage is abruptly reduced. [14] In addition, other drugs with anti-dopaminergic activity, such as the antiemetic metoclopramide, can induce NMS. [15] Tetracyclics with anti-dopaminergic activity have been linked to NMS in case reports, such as the amoxapines. Additionally, desipramine, dothiepin, phenelzine, tetrabenazine, and reserpine have been known to trigger NMS. [16] Whether lithium can cause NMS is unclear. [17] However, concomitant use of lithium is associated with a higher risk of NMS when a person starts on an antipsychotic drug. [18]

At the molecular level, NMS is caused by a sudden, marked reduction in dopamine activity, either from withdrawal of dopaminergic agents or blockade of dopamine receptors. [19]

Risk factors

The use of antipsychotics as well as how this class of medications is used is one of the most common risk factors for NMS. Use of high-potency antipsychotics, a rapid increase in the dosage of antipsychotics, use of long-acting forms of antipsychotics (such as haloperidol) or injectable formulations, or using multiple antipsychotics are all known to increase the risk of developing NMS. [20] [21] [7] Dehydration is a risk factor for the development of NMS. [7] There appears to be no relationship between duration of therapy and the development of NMS. [6]

Use of the following agents is most commonly associated with the development of NMS: [9]

It has been purported that there is a genetic risk factor for NMS. [24] In one study, identical twins presented with NMS, and a mother and two of her daughters have presented with NMS in another case. [25]

Demographically, it appears that males, especially those under forty, are at greatest risk for developing NMS, although it is unclear if the increased incidence is a result of greater antipsychotic use in men under forty. [12] It has also been suggested that postpartum women may be at a greater risk for NMS. [26]

Antipsychotic use in those with Lewy body dementia is a risk factor for NMS. These people are extremely sensitive to antipsychotics. As a result, antipsychotics should be used cautiously in all cases of dementia. [27]

Pathophysiology

The mechanism is commonly thought to depend on decreased levels of dopamine activity due to:

It has been proposed that blockade of D2-like (D2, D3 and D4) receptors induce massive glutamate release, generating catatonia, neurotoxicity and myotoxicity. [29] [30] Additionally, the blockade of diverse serotonin receptors by atypical antipsychotics and activation of 5-HT1 receptors by certain of them reduces GABA release and indirectly induces glutamate release, worsening this syndrome. [31]

The muscular symptoms are most likely caused by blockade of the dopamine receptor D2, leading to abnormal function of the basal ganglia similar to that seen in Parkinson's disease. [32]

In the past, research and clinical studies seemed to corroborate the D2 receptor blockade theory in which antipsychotic drugs were thought to significantly reduce dopamine activity by blocking the D2 receptors associated with this neurotransmitter. The introduction of atypical antipsychotic drugs, with lower affinity to the D2 dopamine receptors, was thought to have reduced the incidence of NMS. However, recent studies suggest that the decrease in mortality may be the result of increased physician awareness and earlier initiation of treatment rather than the action of the drugs themselves. [33] NMS induced by atypical drugs also resembles "classical" NMS (induced by "typical" antipsychotic drugs), further casting doubt on the overall superiority of these drugs. [34]

However, the failure of D2 dopamine receptor antagonism, or dopamine receptor dysfunction, do not fully explain the presenting symptoms and signs of NMS, as well as the occurrence of NMS with atypical antipsychotic drugs with lower D2 dopamine activity. [33] This has led to the hypothesis of sympathoadrenal hyperactivity (results from removing tonic inhibition from the sympathetic nervous system) as a mechanism for NMS. [35] Release of calcium is increased from the sarcoplasmic reticulum with antipsychotic usage. This can result in increased muscle contractility, which can play a role in the breakdown of muscle, muscle rigidity, and hyperthermia. Some antipsychotic drugs, such as typical antipsychotics, are known to block dopamine receptors; other studies have shown that when drugs supplying dopamine are withdrawn, symptoms similar to NMS present themselves. [4]

In support of the sympathoadrenal hyperactivity model, it has been hypothesized that a defect in calcium regulatory proteins within the sympathetic neurons may bring about the onset of NMS. [36] This model of NMS strengthens its suspected association with malignant hyperthermia in which NMS may be regarded as a neurogenic form of this condition which itself is linked to defective calcium-related proteins.[ citation needed ]

There is also thought to be considerable overlap between malignant catatonia and NMS in their pathophysiology, the former being idiopathic and the latter being the drug-induced form of the same syndrome. [37]

The raised white blood cell count and creatine phosphokinase (CPK) plasma concentration seen in those with NMS is due to increased muscular activity and rhabdomyolysis (destruction of muscle tissue). [38] Someone may experience hypertensive crisis and metabolic acidosis.

The fever seen with NMS is believed to be caused by hypothalamic dopamine receptor blockade. Antipsychotics cause an increased calcium release from the sarcoplasmic reticulum of muscle cells which can result in rigidity and eventual cell breakdown. No major studies have reported an explanation for the abnormal EEG, but it is likely also attributable to dopamine blockage leading to changes in neuronal pathways. [12]

Diagnosis

Differential diagnosis

Due to the comparative rarity of NMS, it is often overlooked. Immediate treatment for the syndrome should not be delayed as it has a high mortality of between 10-20%. [39] Differentiating NMS from other neurological disorders can be very difficult.

The diagnosis is suggested on patients with a history of drug exposure to the most common inducing agents such as strong antidopaminergic medications. [6] [40] The differential diagnosis includes serotonin syndrome, [41] encephalitis, toxic encephalopathy, status epilepticus, heat stroke, catatonia and malignant hyperthermia. Drugs such as cocaine and amphetamine may also produce similar symptoms. [4] [42] [6] Features which distinguish NMS from serotonin syndrome include bradykinesia, muscle rigidity, and a high white blood cell count. [43]

Treatment

NMS is a medical emergency and can lead to death if untreated. The first step is to stop the culprit medication and treat the hyperthermia aggressively, such as with cooling blankets or ice packs to the axillae and groin. Acetaminophen is commonly used as an anti-pyretic. Supportive care in an intensive care unit capable of circulatory and ventilatory support is crucial. In those unable to control their secretions, or who have muscle spams of the respiratory muscles, mechanical ventilation may be needed. [7]

The best pharmacological treatment is still unclear. Dantrolene has been used when needed to reduce muscle rigidity, and dopamine pathway medications such as bromocriptine have shown benefit. [44] Dantrolene may act centrally on thermoregulatory pathways to lower the temperature. [7] Dantrolene also inhibits calcium release from the muscle sarcoplasmic reticulum to cause muscle relaxation. [7] Amantadine is another treatment option due to its dopaminergic and anticholinergic effects. Apomorphine may be used however its use is supported by little evidence. [32] Benzodiazepines may be used to control agitation. Highly elevated blood myoglobin levels from muscle breakdown (rhabdomyolysis) can result in kidney damage, therefore aggressive intravenous hydration with diuresis may be required. When recognized early NMS can be successfully managed; however, up to 10% of cases can be fatal. [4]

Should the affected person subsequently require an antipsychotic, trialing a low dose of a low-potency atypical antipsychotic is recommended. [4]

Electroconvulsive therapy may be used in life threatening cases of NMS that are refractory to first line treatments. [7]

Prognosis

The prognosis is best when identified early and treated aggressively. In earlier studies the mortality rates of NMS ranged from 20%–38%, but by 2009 mortality rates were reported to have fallen below 10% over the previous two decades due to early recognition and improvements in management. [45] Re-introduction of antipsychotics after NMS may trigger a recurrence, although in most cases it does not. With recurrence rate being 4.2% in a small, population based study. [7] [46]

Epidemiology

Pooled data suggest the incidence of NMS is between 0.2%–3.23%. [47] However, greater awareness coupled with increased use of atypical anti-psychotics have likely reduced the prevalence of NMS. [12] Additionally, young males are particularly susceptible and the male to female ratio has been reported to be as high as 2:1. [12] [47] [48]

History

NMS was known about as early as 1956, shortly after the introduction of the first phenothiazines. [49] [ self-published source? ] NMS was first described in 1960 by French clinicians who had been working on a study involving haloperidol. They characterized the condition that was associated with the side effects of haloperidol "syndrome malin des neuroleptiques", which was translated to neuroleptic malignant syndrome. [16]

Related Research Articles

<span class="mw-page-title-main">Antipsychotic</span> Class of medications

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<span class="mw-page-title-main">Catatonia</span> Psychiatric behavioural syndrome

Catatonia is a complex syndrome, most commonly seen in people with underlying mood or psychotic disorders. People with catatonia have abnormal movement and behaviors, which vary from person to person and fluctuate in intensity within a single episode. People with catatonia appear withdrawn, meaning that they do not interact with the outside world and have difficulty processing information. They may be nearly motionless for days on end or perform repetitive purposeless movements. Two people may exhibit very different sets of behaviors and both still be diagnosed with catatonia. There are different subtypes of catatonia, which represent groups of symptoms that commonly occur together. These include akinetic catatonia, excited catatonia, malignant catatonia, and delirious mania.

<span class="mw-page-title-main">Serotonin syndrome</span> Symptoms caused by an excess of serotonin in the central nervous system

Serotonin syndrome (SS) is a group of symptoms that may occur with the use of certain serotonergic medications or drugs. The symptoms can range from mild to severe, and are potentially fatal. Symptoms in mild cases include high blood pressure and a fast heart rate; usually without a fever. Symptoms in moderate cases include high body temperature, agitation, increased reflexes, tremor, sweating, dilated pupils, and diarrhea. In severe cases, body temperature can increase to greater than 41.1 °C (106.0 °F). Complications may include seizures and extensive muscle breakdown.

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References

  1. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Berman, Brian D. (January 2011). "Neuroleptic malignant syndrome: a review for neurohospitalists". The Neurohospitalist. 1 (1). New York City: SAGE Publications: 41–47. doi:10.1177/1941875210386491. PMC   3726098 . PMID   23983836.
  2. 1 2 3 4 5 6 7 8 9 10 "Neuroleptic Malignant Syndrome". NORD (National Organization for Rare Disorders). 2004. Archived from the original on 19 February 2017. Retrieved 1 July 2017.
  3. 1 2 3 "Neuroleptic Malignant Syndrome Information Page". Bethesda, Maryland: National Institute of Neurological Disorders and Stroke. Archived from the original on 4 July 2017. Retrieved 1 July 2017.
  4. 1 2 3 4 5 6 7 8 9 Strawn JR, Keck PE, Caroff SN (June 2007). "Neuroleptic malignant syndrome". The American Journal of Psychiatry . 164 (6): 870–876. doi:10.1176/ajp.2007.164.6.870. PMID   17541044.
  5. 1 2 New, Andrea M.; Nelson, Sarah; Leung, Jonathan G. (October 1, 2015). "Psychiatric Emergencies in the Intensive Care Unit". AACN Advanced Critical Care . 26 (4). Aliso Viejo, California: American Association of Critical-Care Nurses: 285–293. doi:10.4037/NCI.0000000000000104. PMID   26484986.
  6. 1 2 3 4 Troller, Julian N.; Chen, Xiaohua; Sachdev, Perminder S. (February 2009). "Neuroleptic malignant syndrome associated with atypical antipsychotic drugs". CNS Drugs . 23 (6). New York City: Springer Nature: 477–92. doi:10.2165/00023210-200923060-00003. PMID   19480467. S2CID   43859486.
  7. 1 2 3 4 5 6 7 8 9 10 11 12 13 Wijdicks, Eelco F.M.; Ropper, Allan H. (26 September 2024). "Neuroleptic Malignant Syndrome". New England Journal of Medicine. 391 (12): 1130–1138. doi:10.1056/NEJMra2404606. PMID   39321364.
  8. Sahin, Aynur; Cicek, Mustafa; Cekic, Ozgen Gonenc; Gunaydin, Mucahit; Aykut, Demet Saglam; Tatli, Ozgur; Karaca, Yunus; Arici, Mualla Aylin (December 2017). "A retrospective analysis of cases with neuroleptic malignant syndrome and an evaluation of risk factors for mortality". Turkish Journal of Emergency Medicine. 17 (4). Ankara, Turkey: Emergency Medicine Association of Turkey: 141–145. doi:10.1016/j.tjem.2017.10.001. PMC   5812912 . PMID   29464217.
  9. 1 2 3 4 5 Simon LV, Hashmi MF, Callahan AL (August 2022). "Neuroleptic Malignant Syndrome.". StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing. PMID   29489248.
  10. 1 2 Papadakis MA, McPhee SJ (2023). "Neuroleptic malignant syndrome.". Quick Medical Diagnosis & Treatment. McGraw Hill.
  11. Milbouer S. "Quest for the truth". Nashua Telegraph. Archived from the original on 2007-09-27.
  12. 1 2 3 4 5 Neuroleptic Malignant Syndrome at eMedicine
  13. Khaldi S, Kornreich C, Choubani Z, Gourevitch R (December 2008). "[Neuroleptic malignant syndrome and atypical antipsychotics: a brief review]" [Neuroleptic malignant syndrome and atypical antipsychotics: A brief review]. L'Encephale (in French). 34 (6): 618–624. doi:10.1016/j.encep.2007.11.007. PMID   19081460.
  14. Keyser DL, Rodnitzky RL (April 1991). "Neuroleptic malignant syndrome in Parkinson's disease after withdrawal or alteration of dopaminergic therapy". Archives of Internal Medicine. 151 (4): 794–796. doi:10.1001/archinte.151.4.794. PMID   1672810.
  15. Friedman LS, Weinrauch LA, D'Elia JA (August 1987). "Metoclopramide-induced neuroleptic malignant syndrome". Archives of Internal Medicine. 147 (8): 1495–1497. doi:10.1001/archinte.147.8.1495. PMID   3632154.
  16. 1 2 Buckley PF, Hutchinson M (March 1995). "Neuroleptic malignant syndrome". Journal of Neurology, Neurosurgery, and Psychiatry. 58 (3): 271–273. doi:10.1136/jnnp.58.3.271. PMC   1073359 . PMID   7897404.
  17. Aronson JK (2015). Meyler's Side Effects of Drugs: The International Encyclopedia of Adverse Drug Reactions and Interactions. Elsevier. p. 607. ISBN   978-0-444-53716-4.
  18. Buckley PF, Hutchinson M (March 1995). "Neuroleptic malignant syndrome". Journal of Neurology, Neurosurgery, and Psychiatry. 58 (3): 271–273. doi:10.1136/jnnp.58.3.271. PMC   1073359 . PMID   7897404.
  19. "Treatment of Schizophrenia". TMedWeb: Medical Pharmacology. Tulane University. Retrieved 2021-06-19.
  20. Miller CS, Wiese JG (2017). "Hyperthermia and fever.". In McKean SC, Ross JJ, Dressler DD, Scheurer DB (eds.). Principles and Practice of Hospital Medicine (2nd ed.). McGraw Hill. ISBN   978-0-07-184313-3.
  21. Keck PE, Pope HG, Cohen BM, McElroy SL, Nierenberg AA (October 1989). "Risk factors for neuroleptic malignant syndrome. A case-control study". Archives of General Psychiatry. 46 (10): 914–918. doi:10.1001/archpsyc.1989.01810100056011. PMID   2572206.
  22. Huppert LA, Dyster TG (2021). "Key medications & interventions in psychiatry.". Huppert's Notes: Pathophysiology and Clinical Pearls for Internal Medicine. McGraw Hill. ISBN   978-1-260-47007-9.
  23. Butterworth IV JF, Mackey DC, Wasnick JD (2022). "Thermoregulation, hypothermia, & malignant hyperthermia.". Morgan & Mikhail's Clinical Anesthesiology (7th ed.). McGraw Hill. ISBN   978-1-260-47379-7.
  24. Velamoor VR (July 1998). "Neuroleptic malignant syndrome. Recognition, prevention and management". Drug Safety. 19 (1): 73–82. doi:10.2165/00002018-199819010-00006. PMID   9673859. S2CID   23303714.
  25. Otani K, Horiuchi M, Kondo T, Kaneko S, Fukushima Y (June 1991). "Is the predisposition to neuroleptic malignant syndrome genetically transmitted?". The British Journal of Psychiatry. 158 (6): 850–853. doi:10.1192/bjp.158.6.850. PMID   1678666. S2CID   23185221.
  26. Alexander PJ, Thomas RM, Das A (May 1998). "Is risk of neuroleptic malignant syndrome increased in the postpartum period?". The Journal of Clinical Psychiatry. 59 (5): 254–255. doi: 10.4088/JCP.v59n0509a . PMID   9632037.
  27. Steinberg M, Lyketsos CG (September 2012). "Atypical antipsychotic use in patients with dementia: managing safety concerns". The American Journal of Psychiatry. 169 (9): 900–906. doi:10.1176/appi.ajp.2012.12030342. PMC   3516138 . PMID   22952071.
  28. Mihara K, Kondo T, Suzuki A, Yasui-Furukori N, Ono S, Sano A, et al. (February 2003). "Relationship between functional dopamine D2 and D3 receptors gene polymorphisms and neuroleptic malignant syndrome". American Journal of Medical Genetics. Part B, Neuropsychiatric Genetics. 117B (1): 57–60. doi:10.1002/ajmg.b.10025. PMID   12555236. S2CID   44866985.
  29. Kornhuber J, Weller M, Riederer P (1993). "Glutamate receptor antagonists for neuroleptic malignant syndrome and akinetic hyperthermic parkinsonian crisis". Journal of Neural Transmission. Parkinson's Disease and Dementia Section. 6 (1): 63–72. doi:10.1007/bf02252624. PMID   8105799. S2CID   45530847.
  30. Chatterjee A (January 2014). "Glutamate-based magnetic resonance spectroscopy in neuroleptic malignant syndrome". Annals of Indian Academy of Neurology. 17 (1): 123–124. doi: 10.4103/0972-2327.128579 . PMC   3992752 . PMID   24753679.
  31. Odagaki Y (January 2009). "Atypical neuroleptic malignant syndrome or serotonin toxicity associated with atypical antipsychotics?". Current Drug Safety. 4 (1): 84–93. CiteSeerX   10.1.1.334.241 . doi:10.2174/157488609787354387. PMID   19149529.
  32. 1 2 Wijdicks EF (26 May 2022). Aminoff MJ, Rabinstein AA, Wilterdink JL (eds.). "Neuroleptic malignant syndrome". UpToDate.
  33. 1 2 Ananth J, Parameswaran S, Gunatilake S, Burgoyne K, Sidhom T (April 2004). "Neuroleptic malignant syndrome and atypical antipsychotic drugs". The Journal of Clinical Psychiatry. 65 (4): 464–470. doi:10.4088/JCP.v65n0403. PMID   15119907. S2CID   32752143.
  34. Hasan S, Buckley P (August 1998). "Novel antipsychotics and the neuroleptic malignant syndrome: a review and critique". The American Journal of Psychiatry. 155 (8): 1113–1116. doi:10.1176/ajp.155.8.1113. PMID   9699705.
  35. Gurrera RJ (February 1999). "Sympathoadrenal hyperactivity and the etiology of neuroleptic malignant syndrome". The American Journal of Psychiatry. 156 (2): 169–180. doi:10.1176/ajp.156.2.169. PMID   9989551. S2CID   31276121.
  36. Gurrera RJ (2002). "Is neuroleptic malignant syndrome a neurogenic form of malignant hyperthermia?". Clinical Neuropharmacology. 25 (4): 183–193. doi:10.1097/00002826-200207000-00001. PMID   12151905. S2CID   29010904.
  37. Northoff G (December 2002). "Catatonia and neuroleptic malignant syndrome: psychopathology and pathophysiology". Journal of Neural Transmission. 109 (12): 1453–1467. CiteSeerX   10.1.1.464.9266 . doi:10.1007/s00702-002-0762-z. PMID   12486486. S2CID   12971112.
  38. Latham J, Campbell D, Nichols W, Mott T (August 2008). "Clinical inquiries. How much can exercise raise creatine kinase level--and does it matter?". The Journal of Family Practice. 57 (8): 545–547. PMID   18687233. Archived from the original on 2016-06-01.
  39. Stringer JL, ed. (2017). "Antipsychotics or neuroleptics.". Basic Concepts in Pharmacology: What You Need to Know for Each Drug Class (5th ed.). McGraw Hill. ISBN   978-1-259-86107-9.
  40. Yandle G, deBoisblanc BP (2014). "Persistent fever". In Hall JB, Schmidt GA, Kress JP (eds.). Principles of Critical Care (4th ed.). McGraw Hill. ISBN   978-0-07-173881-1.
  41. Christensen V, Glenthøj BY (January 2001). "[Malignant neuroleptic syndrome or serotonergic syndrome]". Ugeskrift for Laeger. 163 (3): 301–302. PMID   11219110.
  42. Sachdev PS (June 2005). "A rating scale for neuroleptic malignant syndrome". Psychiatry Research. 135 (3): 249–256. doi:10.1016/j.psychres.2005.05.003. hdl: 1959.4/unsworks_46263 . PMID   15996751. S2CID   25728796.
  43. Birmes P, Coppin D, Schmitt L, Lauque D (May 2003). "Serotonin syndrome: a brief review". CMAJ. 168 (11): 1439–1442. PMC   155963 . PMID   12771076.
  44. Dhib-Jalbut S, Hesselbrock R, Mouradian MM, Means ED (February 1987). "Bromocriptine treatment of neuroleptic malignant syndrome". The Journal of Clinical Psychiatry. 48 (2): 69–73. PMID   3804991.
  45. Ahuja N, Cole AJ (2009). "Hyperthermia syndromes in psychiatry". Advances in Psychiatric Treatment. 15 (3): 181–91. doi: 10.1192/apt.bp.107.005090 .
  46. Guinart, Daniel; Taipale, Heidi; Rubio, Jose M; Tanskanen, Antti; Correll, Christoph U; Tiihonen, Jari; Kane, John M (21 October 2021). "Risk Factors, Incidence, and Outcomes of Neuroleptic Malignant Syndrome on Long-Acting Injectable vs Oral Antipsychotics in a Nationwide Schizophrenia Cohort". Schizophrenia Bulletin. 47 (6): 1621–1630. doi:10.1093/schbul/sbab062. PMC   8530388 . PMID   34013325.
  47. 1 2 Pelonero AL, Levenson JL, Pandurangi AK (September 1998). "Neuroleptic malignant syndrome: a review". Psychiatric Services. 49 (9): 1163–1172. doi:10.1176/ps.49.9.1163. PMID   9735957.
  48. Hernández JL, Palacios-Araus L, Echevarría S, Herrán A, Campo JF, Riancho JA (December 1997). "Neuroleptic malignant syndrome in the acquired immunodeficiency syndrome". Postgraduate Medical Journal. 73 (866): 779–784. doi:10.1136/pgmj.73.866.779. PMC   2431511 . PMID   9497946.
  49. Friedberg JM. "Neuroleptic malignant syndrome". Archived from the original on October 16, 2006. Retrieved 2006-07-03.[ self-published source ]