The goal of skin cleansing is to remove dirt and prevent odor, but actual hygienic practices are influenced by skin type, lifestyle, and culture. Extensive bathing aggravates dry skin, and hot baths cause vasodilation, which further promotes itching. Many soaps are salts of fatty acids with an alkali base. Soap is a degreaser and can also irritate skin. Older adults or individuals with dry skin should limit use of soaps to those areas with apocrine glands. Plain water should suffice for other skin surfaces. Mild soaps have less soap or detergent content. Superfatted soaps deposit a film of oil on the skin surface, but there is no proof that they are less drying than other soaps and they may be more expensive.
Tepid baths have an antipruritic effect, possibly resulting from capillary vasoconstriction. The bath should be limited to a half hour every day or every two days. Examples of mild soaps that can be recommended include Dove, Neutrogena, and Basis. Oil can be added to the water at the end of the bath or applied to the skin before towel drying.
Heat increases cutaneous blood flow and may enhance itching. Heat also lowers humidity, and skin loses moisture when the relative humidity is less than 40%. A cool, humid environment may reverse these processes.
Residue left by detergents used in laundering clothes and linens, as well as fabric softeners and antistatic products, may aggravate pruritus. Detergent residue can be neutralized by the addition of vinegar (1 teaspoon per quart of water) to rinse water. Mild laundry soaps marketed for infant items may offer a solution as well.
Loose-fitting, lightweight cotton clothes and cotton bed sheets are suggested. The elimination of heavy bedcovers may alleviate itching by decreasing body heat. Wool and some synthetic fabrics may be irritating. Distraction, music therapy, relaxation, and imagery may be useful to relieve symptoms.
If treatment of the underlying disease and/or control of other aggravating factors provides inadequate relief of pruritus, topical and oral medications may be useful. Topical steroids may provide relief when symptoms are related to a steroid-responsive dermatosis, but anticipated benefits must be weighed against the vasoconstrictive side effects. Topical steroids have no role in the management of pruritus of unknown origin. Topical steroids should not be applied to skin surfaces inside a radiation treatment field.
Systemic medications useful in the management of pruritus include those directed toward the underlying disease or control of symptoms. Antibiotics can reduce symptoms associated with infection. Oral antihistamines may provide symptomatic relief in histamine-related itching. A higher dose of antihistamines at bedtime may produce antipruritic and sedative effects. Diphenhydramine hydrochloride, 25 mg to 50 mg every 6 hours, has demonstrated effectiveness.[Level of evidence: IV] Hydroxyzine hydrochloride, 25 mg to 50 mg every 6 to 8 hours, or cyproheptadine hydrochloride, 4 mg every 6 to 8 hours, may provide symptomatic relief. Oral chlorpheniramine (4 mg) or hydroxyzine (10 mg or 25 mg) orally every 4 to 6 hours has been used with good results.[Level of evidence: IV] If one antihistamine is ineffective, one of another class may provide relief.