July 2006, Volume 36 Number 7 , p 17 - 17
PRURITUS IS ONE OF THE most common symptoms of patients with dermatologic disorders. Itch receptors are unmyelinated brushlike nerve endings found exclusively in the skin, mucous membranes, and cornea. Although pruritus usually is caused by primary skin disease and accompanied by a rash or lesions, it can occur without rash or lesions. This is referred to as essential pruritus, which generally has a rapid onset, may be severe, and interferes with normal daily activities.
Scratching the itchy area causes the inflamed cells and nerve endings to release histamine, producing more pruritus and generating a vicious itch-scratch cycle. The patient's skin integrity may be altered, causing excoriation, redness, wheals, infection, or changes in pigmentation.
Pruritus usually is more severe at night than during the day, probably because the person is distracted by daily activities.
What causes pruritus?
Pruritus may be the first indication of a systemic internal disease such as diabetes, blood disorders, or ...