(1997; 132 pages) [French] [Spanish]
Pruritus or itching is a persistent and distressing symptom of many skin disorders, but it also occurs in apparently healthy people. One of the most common causes in elderly patients is dry skin. Itching can be a major problem wherever humidity is low. In some instances, it may result from the release of histamine from dermal mast cells, in which case antihistamines are specifically indicated. However, this is uncommon, and it is important to rule out common causes such as scabies, lice and fleas.
Non-specific pruritus, unaccompanied by other evidence of skin disease, is commonly diffuse and often aggravated by restrictive clothing. In temperate climates, it is often exacerbated by warm weather. Elderly patients in particular should be examined to exclude specific skin conditions and pruritus associated with obstructive liver disease, severe diabetes, advanced uraemia or lymphoproliferative disorders. Itching is also a cutaneous symptom of AIDS.
If a cause can be found, this should be corrected. Emollients such as aqueous creams or frequent applications of calamine lotion often provide relief. Hydrocortisone applied sparingly and intermittently in low concentrations sometimes provides additional relief when the sensation remains troublesome. Systemic antihistamines may be helpful in severe cases, but their activity is probably due to their sedating effect.