Those Itchy Bumps Could Be Scabies Some patients who visit the pharmacy seeking relief from what appears to be insect bites may actually be suffering from scabies, an intensely itchy skin infestation caused by a microscopic mite. Scabies epidemics usually last for 15 years, followed by 15 years of relative inactivity. However, the most recent outbreak of scabies has continued unabated for 25 years, according to Milton Orkin, MD, clinical professor of dermatology at the University of Minnesota Medical School and an expert on cutaneous infestations. Scabies occurs when newly fertilized female mites (Sarcoptes scabei) burrow into the skin and lay their eggs, causing pruritis and papular dermatitis. The mites tend to attack warm, soft areas, such as between the fmgers, the wrists, elbow creases, armpits, breasts, abdomen, groin, and buttocks. An infested patient carries 11 of the adult female mites on average. Scabies is spread through prolonged skin-to-skin contact. I t is usually transmitted through sexual activity or between children and parents or patients and medical staff. Although it can be associated with unhygienic conditions, anyone can get scabies, Orkin says, noting that some 300 million cases crop up worldwide each year. The parasite also affects about 2% of AIDS sufferers, appearing in atypical forms that make scabies difficult to diagnose. If scabies infestation is suspected, a physician should take skin scrapings to look for the organism, according to Orkin. "Many times it's important to treat the entire household," he says, because the infection is limited to one person in only 50% of cases. The incubation period is usually four to six weeks, and the organism can be transmit-
ted to others before symptoms appear. Mter successful treatment, the bumps and itching may persist up to four weeks. To treat patients, Orkin and his colleague Harold Maibach, MD (University of California at San Francisco Department of Dermatology) prefer using permethrin 5% cream (Elimite-Herbert Laboratories). "It's an excellent scabicide with low toxicity and no reports of resistance," Orkin says. They also recommend using 6% sulfur in petrolatum for infants under the age of two months and pregnant or nursing women. Lindane, the standard treatment for many years, is usually effective but can cause central nervous system toxicity when misused, Orkin says, noting that the scabies mite also appears to be developing some resistance to it. Patients with scabies should be given these instructions, according to Orkin: • Take a bath or shower in tepidnot hot-water. Then apply the prescribed medication thinly but thor-
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oughly behind the ears and from the neck down, giving special attention to the hands, feet, groin, and area between the toes and buttocks. • Follow the package insert; do not apply more medication than the instructions say, and do not use it more often than prescribed. If you're applying the medication to someone else, wear disposable gloves. • Because mites tend to hide under fingernails, keep them trimmed short and brush the free edge. • Machine wash and dry on hot cycles any underwear, sleepwear, bed linen, and towels used in the previ0us few days. It's not necessary to clean outer wear or furniture, however, since the mites survive only about 48 hours away from the human body.
Health Promotions September National Pediculosis Prevention Month. National Pediculosis Association, P.O. Box 149, Newton, MA 02161. (617) 449-6487. National Cholesterol Education Month. National Heart, Lung, & Blood Institute, NIH Information Center, 4733 Bethesda Ave., Suite 530, Bethesda, MD 20814. (301) 951-3260.
October Talk About Prescriptions Month. National Council on Patient Information and Education, 666 11th St., NW, Suite 810, Washington, DC 20001. (202) 347-6711. National Pharmacy Week, October 2(}"'26. American Pharmaceutical Association, 2215 Constitution Ave., NW, Washington, DC 20037. (202) 628-4410. 17