Hostname: page-component-586b7cd67f-r5fsc Total loading time: 0 Render date: 2024-11-25T20:55:57.705Z Has data issue: false hasContentIssue false

Mechanism of action of narcolepsy medications

Published online by Cambridge University Press:  18 November 2014

Chandan R. Gowda*
Affiliation:
Arizona College of Osteopathic Medicine, Midwestern University, Glendale, Arizona, USA
Leslie P. Lundt
Affiliation:
Santa Barbara County Alcohol, Drug and Mental Health Services, Psychiatric Health Facility, Santa Barbara, CA, USA
*
*Address for correspondence: Chandan Gowda, Midwestern University, 19555N 59th Avenue, Glendale, AZ 85308, USA. (Email: [email protected])

Abstract

The medications used to treat narcolepsy are targeted toward alleviating symptoms such as excessive sleepiness and cataplexy. The cause of this neurological sleep disorder is still not completely clear, though a destruction of hypocretin/orexin neurons has been implicated. The destruction of these neurons is linked to inactivity of neurotransmitters including histamine, norepinephrine, acetylcholine, and serotonin, causing a disturbance in the sleep/wake cycles of narcoleptic patients. Stimulants and MAOIs have traditionally been used to counteract excessive daytime sleepiness and sleep attacks by inhibiting the breakdown of catecholamines. Newer drugs, called wake-promoting agents, have recently become first-line agents due to their better side-effect profile, efficacy, and lesser potential for abuse. These agents similarly inhibit reuptake of dopamine, but have a novel mechanism of action, as they have been found to increase neuronal activity in the tuberomamillary nucleus and in orexin neurons. Sodium oxybate, a sodium salt of gamma-hydroxybutyrate (GHB), is another class that is used to treat many symptoms of narcolepsy, and is the only U.S. Food and Drug Administration (FDA)-approved medication for cataplexy. It has a different mechanism of action than either stimulants or wake-promoting agents, as it binds to its own unique receptor. Antidepressants, like selective serotonin re-uptake inhibitors (SSRIs) and tricyclic antidepressants (TCAs), have also been used, as similar to stimulants, they inhibit reuptake of specific catecholamines. In this article, we seek to review the mechanisms behind these classes of drugs in relation to the proposed pathophysiology of narcolepsy. Appropriate clinical strategies will be discussed, including specific combinations of medications that have been shown to be effective.

Type
CME Review Article
Copyright
© Cambridge University Press 2014 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Footnotes

This activity is supported by an educational grant from Jazz Pharmaceuticals, Inc.

References

1.Nishino, S, Ripley, B, Overeem, S, Lammers, GJ, Mignot, . Hypocretin (orexin) deficiency in human narcolepsy. Lancet. 2000; 355(9197): 3940.Google Scholar
2.Kumar, S, Sagili, H. Etiopathogenesis and neurobiology of narcolepsy: a review. J Clin Diagn Res. 2014; 8(2): 190195.Google ScholarPubMed
3.Nishino, S, Okuro, M, Kotorii, N, et al. Hypocretin/orexin and narcolepsy: new basic and clinical insights. Acta Physiol (Oxf). 2010; 198(3): 209222.Google Scholar
4.Nishino, S. The hypothalamic peptidergic system, hypocretin/orexin and vigilance control. Neuropeptides. 2007; 41(3): 117133.Google Scholar
5.Stahl, SM. Stahl's Essential Psychopharmacology: Neuroscientific Basis and Practical Applications. Cambridge, UK: Cambridge University Press; 2008.Google Scholar
6.Siegel, JM. REM sleep. In Kryger MH, Roth T, Dement W, eds. Principles and Practice of Sleep Medicine. Philadelphia: Elsevier Saunders; 2005: 120135.Google Scholar
7.Prinzmetal, M, Bloomberg, W. The use of benzedrine for the treatment of narcolepsy. JAMA. 1935; 105(25): 20512054.CrossRefGoogle Scholar
8.Billiard, M. Narcolepsy: current treatment options and future approaches. Neuropsychiatr Dis Treat. 2008; 4(3): 557566.Google Scholar
9.Mayer, G, Ewert Meier, K, Hephata, K. Selegiline hydrochloride treatment in narcolepsy: a double-blind, placebo-controlled study. Clin Neuropharmacol. 1995; 18(4): 306319.Google Scholar
10.US Modafinil in Narcolepsy Multicenter Study Group. Randomized trial of modafinil for the treatment of pathological somnolence in narcolepsy. Ann Neurol. 1998; 43(1): 8897.Google Scholar
11.Volkow, ND, Fowler, JS, Logan, J, et al. Effects of modafinil on dopamine and dopamine transporters in the male human brain: clinical implications. JAMA. 2009; 301(11): 11481154.Google Scholar
12.Scammell, TE, Estabrooke, IV, McCarthy, MT, et al. Hypothalamic arousal regions are activated during modafinil-induced wakefulness. J Neurosci. 2000; 20(22): 86208628.Google Scholar
13.Darwish, M, Kirby, M, Hellriegel, ET. Comparison of steady-state plasma concentrations of armodafinil and modafinil late in the day following morning administration. Clin Drug Investig. 2009; 29(9): 601612.CrossRefGoogle ScholarPubMed
14.Mignot, EJM. A practical guide to the therapy of narcolepsy and hypersomnia syndromes. Neurotherapeutics. 2012; 9(4): 739752.CrossRefGoogle Scholar
15.Black, J, Pardi, D, Hornfeldt, CS, Inhaber, N. The nightly use of sodium oxybate is associated with a reduction in nocturnal sleep disruption: a double-blind, placebo-controlled study in patients with narcolepsy. J Clin Sleep Med. 2010; 6(6): 596602.Google Scholar
16.Huang, YS, Guilleminault, C. Narcolepsy: action of two gamma-aminobutyric acid type B agonists, baclofen and sodium oxybate. Pediatr Neurol. 2009; 41(1): 916.Google Scholar
17.Akimoto, H, Honda, Y, Takahashi, Y. Pharmacotherapy in narcolepsy. Dis Nerv Syst. 1960; 21: 704706.Google Scholar
18.Thorpy, M. Therapeutic advances in narcolepsy. Sleep Med.. 2007; 8(4): 427440.Google Scholar
19.Golbin, AZ, Kravitz, HM, Keith, LG. Sleep Psychiatry. London: Taylor & Francis; 2004.Google Scholar
20.Møller, LR, Østergaard, JR. Treatment with venlafaxine in six cases of children with narcolepsy and with cataplexy and hypnagogic hallucinations. J Child Adolesc Psychopharmacol. 2009; 19(2): 197201.CrossRefGoogle ScholarPubMed
21.Black, J, Houghton, WC. Sodium oxybate improves excessive daytime sleepiness in narcolepsy. Sleep. 2006; 29(7): 939946.CrossRefGoogle ScholarPubMed