Narcolepsy (part 6)

… continued from previous five articles on narcolepsy, where the recent article mentioned the side effects of some pharmacological treatments.

My focus in the next few articles will be on the effects of the pharmacological treatments (mentioned in the previous articles) on the body.

In this week’s article, I will discuss the effects of antidepressants on one’s body.

What are the effects of the drugs on the body?

The pharmacological treatments mentioned in the previous articles have quite a few side effects (also mentioned in the previous article). However, some drugs do not have very dangerous side effects when compared to the rest. Nevertheless, they can still cause one further discomfort like stomach aches, dizziness, nervousness. These side effects especially the latter, might affect self-confidence as well as task performance.

Antidepressants:

The first antidepressants available in the 1960s were the tricyclic antidepressants. Their main feature is that they have the capability to inhibit the reuptake of norepinephrine (NE) and 5-serotonin (5-HT) at the nerve endings. For cataplexy treatment, cholinergic and noradrenergic neurotransmitters were used as noradrenergic reuptake inhibition was the main factor to stop cataplectic attacks. Older anti-depressants such as imipramine and protriptyline were the first choice for treatment of cataplexy but their anticholinergic side effects like weight gain, sexual dysfunction and sedation made them less popular. Newer anti-depressants such as fluoxetine, paroxetine, sertraline and citalopam were developed due to their selective serotonergic reuptake hindering properties and became popular for cataplexy treatment.

A benefit of selective serotonin reuptake inhibitors (SSRIs) is that they have fewer side effects compared to the tricyclics also; they can be prescribed to both adults and children. However, disadvantages of tricyclics and SSRIs antidepressants are the risk of development of REM behavior disorder (RBD) as there is reduction of normal REM sleep atonia and REM sleep stage. Also, muscle atonia linked with REM sleep is decreased and so dissociate REM sleep (electroencephalographic pattern of REM sleep without muscle atonia). As a result, one may physically act out their dreams and cause harm to others or himself/herself.

Glossary:
  1. Tricyclic antidepressants Tricyclic antidepressants are used to treat depression. They are also used to treat some other conditions such as migraine, panic disorder, obsessive-compulsive disorder, recurrent headaches, and some forms of pain. The word tricyclic refers to the chemical structure of the medicine.(1)
  1. Norepinephrine (NE) – Norepinephrine is a chemical released from the sympathetic nervous system in response to stress. It is classified as a neurotransmitter, a chemical that is released from neurons. Because the release of norepinephrine affects other organs of the body, it is also referred to as a stress hormone.(2)
  1. Serotonin – Serotonin is a naturally occurring chemical in the brain (a neurotransmitter) that is responsible, in part, for regulating brain functions such as mood, appetite, sleep, and memory.(3)
  1. Cholinergic– 1. parasympathomimetic; stimulated, activated, or transmitted by choline (acetylcholine); said of the sympathetic and parasympathetic nerve fibers that liberate acetylcholine at a synapse when a nerve impulse passes. An agent that produces such an effect.(4)
  1. Noradrenergic- activated by or secreting norepinephrine.(5)
  1. Anticholinergic- parasympatholytic; blocking the passage of impulses through the parasympathetic nerves; also, an agent that so acts.(6)
  2. REM sleep- REM stands for rapid eye movement. During REM sleep, your eyes move quickly in different directions. That doesn’t happen during non-REM sleep. First comes non-REM sleep, followed by a shorter period of REM sleep, and then the cycle starts over again. Dreams typically happen during REM sleep.(7)
  3. REM behavior disorder – REM behavior disorder, also called REM sleep behavior disorder or RBD is a sleeping condition that has always been present, but was only first described in 1986. RBD is considered a sleep disorder which involves unusual actions or behaviors during the rapid eye movement (REM) sleep phase.
    REM behavior disorder is a type of parasomnia. Parasomnias are sleep disorders in which strange or dangerous events occur, that affect or intrude on sleep. Examples include sleep terrors, REM behavior disorder, nocturnal dissociative disorder, somnambulism (sleepwalking), and sleep talking.(8)
  4. Muscle atonia- decreased or absent muscle tone.(9)

To be continued…

 

References:

(6). TheFreeDictionary.com. (2016). anticholinergic. [online] Available at: http://medical-dictionary.thefreedictionary.com/anticholinergic [Accessed 12 Apr. 2016].
(9). TheFreeDictionary.com. (2016). atonia. [online] Available at: http://medical-dictionary.thefreedictionary.com/atonia [Accessed 12 Apr. 2016].
(7). WebMD. (2016). Basics on Sleep. [online] Available at: http://www.webmd.com/sleep-disorders/guide/sleep-101 [Accessed 12 Apr. 2016].
(4). TheFreeDictionary.com. (2016). cholinergic. [online] Available at: http://medical-dictionary.thefreedictionary.com/cholinergic [Accessed 12 Apr. 2016].
(3). Kristalyn Salters-Pedneault, P. (2016). Feeling Low? It Could Be Your Serotonin Level. Find out more.. [online] About.com Health. Available at: http://bpd.about.com/od/glossary/g/serotonin.htm [Accessed 12 Apr. 2016].
(5). TheFreeDictionary.com. (2016). noradrenergic. [online] Available at: http://medical-dictionary.thefreedictionary.com/noradrenergic [Accessed 12 Apr. 2016].
(1). TheFreeDictionary.com. (2016). tricyclic antidepressants. [online] Available at: http://medical-dictionary.thefreedictionary.com/tricyclic+antidepressants [Accessed 12 Apr. 2016].
(2). Study.com. (2016). What Is Norepinephrine? – Effects, Function & Definition – Video & Lesson Transcript | Study.com. [online] Available at: http://education-portal.com/academy/lesson/what-is-norepinephrine-effects-function-definition.html [Accessed 12 Apr. 2016].
(8). Medical News Today. (2012). What is REM behavior disorder?. [online] Available at: http://www.medicalnewstoday.com/articles/247730.php [Accessed 12 Apr. 2016]. 

 

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