Restless leg syndrome

The retinoids comprise a family of polyisoprenoid lipids that inclndes vitamin A (retinol) and stracturaUy related componnds. The biological activity of retinoids can be mod-ihed, for example, by changes in the molecules state of oxidation and cis/trans isomerization. Their activity is also dependent on the levels of specific types of retinoid-binding proteins that exist in extracellular, cytosolic, and nuclear compartments. The role of retinoids in gene expression represents an important biological function for this family of molecules. Retinoid-dependent modulation of gene expression is critical for normal cell and tissue function in mature as well as developing animals. 

Rh (D) immune globulin IV (human) (RhIVIG) is an immune globulin. By binding Rho(D) antigen and red blood cells, RhIGIV prevents production of anti-Rho(D) antibodies in 

Rho(D) inunune globulin is indicated whenever fetal red blood cells are known or suspected to have entered the circulation of an Rh-negative mother unless the fetus is known also to be Rh-negative. The drug is given intramuscularly. The half-life of circulating immunoglobulin is approximately 21 to 29 days. 

Injection-site discomfort and low-grade fever have been reported. Systemic reactions are extremely rare, but myalgia, lethargy, and anaphylactic shock have been reported. As with all plasma-derived products, there is a theoretical risk of transmission of infectious disease. 

Intravenous immunoglobulin (IVIC) In recent years indications for the use of intravenous immunoglobulin (IVIG) have expanded beyond replacement therapy for agammaglobulinemia and other immunodeficiencies to 

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Measurement of muscle activity, usually measured by electrodes placed on the skin. The EMG is used in sleep research to aid in the discrimination of sleep stages, and also as part of diagnosis of sleep disorders such as periodic limb movements and restless legs syndrome. 

Restless legs syndrome, also known as Ekbom s syndrome, causes unpleasant sensations in the legs such as tingling, discomfort and sometimes pain. Symptoms are usually worse at night and disturb sleep. Resting usually makes symptoms worse and activity relieves the condition. The cause of the condition is currently unknown but it is common and usually occurs in middle age. There are currently few treatments in place. 

S = Sleep disturbances (insomnia, rapid eye movement sleep behavioral disorder, restless legs syndrome)... 

Describe the mechanisms of the sleep disorders covered in this chapter, including insomnia, narcolepsy, restless-legs syndrome, obstructive sleep apnea, and parasomnias. 

Restless-legs syndrome treatment involves suppression of abnormal sensations and leg movements and consolidation of sleep. Dopaminergic and sedative-hypnotic medications are prescribed commonly. 

Restless-legs syndrome occurs in 5% to 15% of the population, making it a common sleep disorder.11,12 The prevalence of RLS increases with age and in various medical conditions such as end-stage renal disease (ESRD), pregnancy, and iron deficiency.13 RLS appears to be more common in women than in men and has a genetic link. The majority of RLS patients (63% to 92%) report a positive family history.14... 

Restless-Legs Syndrome and Periodic Limb Movements of Sleep (PLMS)... 

FIGURE 38-1. Primary assessment and initial treatment for complaint of excessive daytime sleepiness. RLS, restless-legs syndrome NPSG, nocturnal polysomnography OSA, obstructive sleep apnea DA, dopamine agonist MSLT, multiple sleep latency test BZDRA, benzodiazepine receptor agonist SNRI, serotonin and norepinephrine reuptake inhibitor TCA, tricyclic antidepressant CPAP, continuous positive airway pressure. 

OSA obstructive sleep apnea Hening WA, Allen RP, Earley CJ, et al. Restless Legs Syndrome Task... 

RDP respiratory disturbance index treatment of restless legs syndrome and periodic limb move-... 

The authors thank Drs Shawn Hochman and David Weinshenker for their insightful comments and expertise that contributed to this work. Special thanks to our close colleagues Drs Glenda Keating and Michael Decker, who contributed much to the body of this work. Dr Rye is supported by USPHS grants NS-36977, NS-40221, and NS-43374, and the Restless Legs Syndrome and Arthur L. Williams Jr. Foundations. 

Clemens S., Rye D., Hochman S. (2006). Restless legs syndrome revisiting the dopamine hypothesis from the spinal cord perspective. Neurology 67, 125-30. 

Garcia-Borreguero D., Larrosa O., Saiz T. et al. (2001). Circadian variation in neuroendocrine response to the administration of L-dopa in patients with restless legs syndrome a pilot study. Sleep 24(suppl.), (A16-A17). 

One of the metabolites of bupropion, radafaxine (GW 353162, 25), is being studied as a treatment for obesity in clinic trials [76]. It is also reported to be in clinical development for restless leg syndrome, neuropathic pain, bipolar disorder and fibromyalgia [68]. 

The recent approval of the SNRI duloxetine for the treatment of diabetic neuropathy reinforces the utility of this drug class in the treatment of neuropathic pain. Other largely untapped areas which remain to be exploited with this drug class include sexual dysfunction, such as premature ejaculation, irritable bowel syndrome, obesity, neurodegenerative diseases such as Parkinson s disease, restless leg syndrome, and substance abuse and addiction. It is apparent that considerable opportunities for drug discovery will exist in this area for some time to come. 

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