An allergic skin rash is an immune reaction to allergy-causing substances. On contact or exposure to an irritating or harmless substance, the immune system over-reacts by releasing chemicals and antibodies that cause the skin to develop a rash. Dry, irritated skin may exacerbate the problem, but proper management and treatment can make life bearable for people suffering from an allergic skin rash.
Types
Allergic contact dermatitis occurs when the skin comes into direct contact with an allergen and produces a rash. Others develop an allergic skin rash known as atopic dermatitis, or eczema, when they eat, handle or are exposed to certain allergy-causing substances. Unlike people with contact allergies, those with eczema may react merely by being exposed to the allergy-causing substance, notes the American Academy of Allergy, Asthma & Immunology. For instance, one person may develop a contact rash from wearing latex gloves, while another may develop eczema rash from accidentally inhaling house dust. The same person may have allergic contact dermatitis and atopic dermatitis.
Allergens
A person with contact dermatitis may experience rash on contact with latex, hair dyes, nickel, perfumes, preservatives, solvents, soaps and some plants. According to the Merck Manual Medical Library, even creams and lotions for treating dermatitis may cause an allergic rash in some people. Poison ivy is a common cause of allergic contact dermatitis. A person with eczema may react to food such as eggs, milk, wheat, nuts, shellfish and airborne allergens like dust, pollen or animal dander, according to the AAAAI.
Symptoms
An allergic skin rash is usually very itchy and may appear swollen or irritated. In infants, atopic dermatitis may appear first as an itchy rash around the face and neck, while the rash may appear on the back of the hands, elbows and knees in older children and adults. Eczema rash may become brown and crusty and may ooze with fluid. Rashes from contact allergies are usually localized to the hands or body part that had direct contact. Contact rash may burn or sting and develop blisters or pimples.
Treatment
Physicians may treat an allergic skin rash with topical antihistamines and calamine lotion to relieve itching, swelling and inflammation or oral corticosteroids to block the action of chemicals of the immune system and reduce skin inflammation. However, the Asthma and Allergy Foundation of America cautions against the long-term use of corticosteroids since it can cause flare-ups when the medication is stopped. Antibiotics may help treat the infections from complications.
Self-Care
The best way to prevent a rash from worsening is to avoid substances that can cause flare-ups. Frequent warm baths and hypoallergenic moisturizers will keep the skin moist. Longer breastfeeding and delaying solid foods may also prevent the development of food allergies in infants. Keeping the fingernails trimmed or putting on gloves at night may also prevent a child from scratching the skin.
