Scabies causes severe itching, especially at night, when there are fewer distractions. (It is sometimes called the “7-year itch” because it probably lasts 7 years without treatment.) The eruption is characterized by small, 2- to 5-mm red papules that are predominantly found in intertriginous or warm and protected areas such as the finger webs (Fig. 4-1), inframammary areas, and axillae. It is caused by the mite, Sarcoptes scabiei. The pathognomonic lesion is the burrow, a brownish, irregular line with scaling at one end and sometimes a vesicle at the other end. Unfortunately, the burrow is often hard to find. Another common site is the penis. Lesions can also appear on the trunk and extremities, but rarely on the face except in children or in immunocompromised patients. The papules sometimes are eczematized and secondarily infected as the result of scratching to alleviate the marked nocturnal itching.