ABSTRACT
Pruritus or itch is the most common symptom of dermatologic disease and a primary symptom in the interface between sleep and dermatology. The frequency of sweating is highest during nonrapid eye movement sleep, especially slow-wave sleep, and lowest during rapid eye movement periods. The frequency of scratching during the different sleep stages appears to be proportional to the relative level of sympathetic nervous activity normally observed during the sleep stage. The “biologics” appear to be especially effective in the treatment of sleeprelated complaints. Sleep restriction of 25%–50% of the normal 8-hour sleep period has been associated with an elevation of the mediators of inflammation. The decrease in the core body temperature before the onset of sleep and during sleep is associated with a dilatation of peripheral blood vessels, which facilitates the dissipation of heat from the core to the periphery.
