Sleep disorders drug-induced

Historically, stimulants that increase the activity of catecholamines are the oldest drugs in this group (Jones et al. 1973). Reduction in DA activity has been related to a reduction in wakefulness lesions of DA cell groups in the ventral tegmentum that project to the forebrain have been shown to induce a marked reduction in behavioral arousal in rats (Jones et al. 1973), and patients with Parkinson s disease, who exhibit consistent DA lesions, experience severe sleep disorders (Rye and Jankovic 2002). 

The patient experiences anxiety, apathy, bradyphrenia (slowness of thought processes), confusional state, dementia, depression, hallucinosis/psychosis (typically drug-induced), and sleep disorders (excessive daytime sleepiness, insomnia, obstructive sleep apnea, and rapid eye movement sleep behavior disorder). 

But later, in Phase II, after two years of continuous use, the SSRIs may contribute to a more ominous motor syndrome, the REM sleep behavior disorder described in chapter 8 as the enactment of dreamed movement. Eor reasons still not well understood, the drugs interfere with our normal ability to inhibit motor outputs. As with tardive dyskinesia victims, patients who develop SSRI-induced RBD may find that their sleep disorder does not abate when they discontinue the drug. The RBD can itself be treated with benzodiazepines—Clonazepam, for example. But that may be throwing good drug money after bad. And a more disturbing possibility, not yet observed, is that the SSRI-induced RBD will evolve in the same way that spontaneous RBD does to full-blown Parkinson s disease. 

Secondary insomnia is the most frequent form of insomnia. The determinants of secondary insomnia can be grouped into the following categories (1) mental disorders (2) neurological diseases (3) medical conditions and (4) abuse of drug-or medication-induced sleep disorder [15]. A list of major factors is included as Tab. 1. 

The differential includes a drug-induced psychosis, schizophrenia, schizoaffective disorder and psychotic depression. She is at high risk of self-neglect, further deterioration of mental health and rough sleeping. There is a moderate risk of suicide and violence. 

Now Schenck, Mahowald, and others tell us that not only does SSRI treatment potentiate eye movements in NREM sleep, but that it may also potentiate dream enactment in REM sleep. In other words, SSRIs may induce the REM sleep behavior disorder How does this work In addition to releasing the saccade generator from inhibition, the drug appears to interfere with the spinal cord inhibitory mechanism that normally blocks the central motor commands that so convincingly animate our dreams but do not result in real behavior. 

As well as oral use, i.v. administration (with the pleasurable flash as with opioids) is employed. Severe dependence induces behaviour disorders, hallucinations and even florid psychosis, which can be controlled by haloperidol. Withdrawal is accompanied by lethargy, sleep, desire for food and sometimes severe depression, which leads to an urge to resume the drug. 

Benzodiazepine abuse is different from other substance abuse disorders (opiates, amphetamines, and nicotine) because benzodiazepines cause much less euphoria and do not activate the classic reward systems that are activated with other substances (mainly the mesolimbic and mesocortical dopaminergic projections). In fact, most people do not find the subjective effects of benzodiazepines pleasant beyond their therapeutic anxiolytic or sleep-inducing effects. Therefore, abuse of benzodiazepines is usually secondary to other substance-abuse disorders, with the benzodiazepine being taken for relief from symptoms induced by the use of another drug. As potential drugs of abuse, short-acting benzodiazepines seem to be preferred among addicts because of the rapidity of their onset of action (aiprazoiam, fiunitrazepam, and iorazepam). 

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