Allergic Skin Conditions (overview)

There are several types of allergic skin conditions. They are often itchy and red and may appear scaly, bumpy or swollen. An allergist can determine which condition you have and develop a treatment plan to help you feel better.

While skin allergies are unpleasant and troublesome, there are things you can do to treat them.

Hives and Angioedema
Hives (or urticaria) are red, itchy, raised areas of the skin that can range in size and appear anywhere on your body. Most common are acute cases, where food or drug allergies are triggers. These hives usually go away within a few days. In cases of chronic hives (lasting more than six weeks), people may suffer for months to years.

Angioedema is a swelling of the deeper layers of the skin that sometimes occurs with hives. The areas often involved are the eyelids, lips, tongue, hands and feet.

Food or drug reactions are a common cause of acute hives and/or angioedema. Viral or bacterial infection can also trigger hives in both adults and children. Physical urticaria are hives resulting from a non-allergic source: rubbing of the skin, cold, heat, physical exertion or exercise, pressure and direct exposure to sunlight.

If the cause of your hives can be identified, you should avoid that trigger. With acute hives, some drugs or foods may take days to leave the body, so your allergist may prescribe antihistamines to relieve your symptoms until that happens.

Contact Dermatitis
When certain substances come into contact with your skin, they may cause an eczema-like rash. There are two types of contact dermatitis: allergic and irritant. Irritant contact dermatitis is caused by substances that cause burning, itching or redness in all people if the exposure dose or duration is long enough. It is a common problem in people who wash there hands too frequently. An example of allergic contact dermatitis is the itchy, red, blistered reaction experienced by some people after contact with poison ivy. This allergic reaction is caused by a chemical in the plant called urushiol. Only some people will react with this chemical and is some cases, the reaction is severe. You can have a reaction from touching other items the plant has come into contact with. Allergic contact dermatitis reactions can happen 24 to 48 hours after contact. Once a reaction starts, it takes 14 to 28 days to go away, even with treatment.

Other common cause of allergic contact dermatitis include nckel, perfumes, dyes, rubber (latex) products and cosmetics also frequently. Some ingredients in medications applied to the skin can cause a reaction, most commonly neomycin, an ingredient in antibiotic creams. For irritant contact dermatitis, you should avoid the substance causing the reaction. Gloves can sometimes be helpful. Since these reactions are non-allergic, avoiding the substance will relieve your symptoms and prevent lasting damage to your skin.

Treatment for allergic contact dermatitis depends on identifing and avoiding the offending agent. If the allergen can not be readilly determined by history, allergy patch tests may be used to help identify it. To relieve symptoms, you may be prescribed topical a corticosteroid cream and in severer cases, an oral corticosteroid for a few days may be required.

Atopic Dermatitis
A common allergic reaction often affecting the face, elbows and knees is atopic dermatitis or eczema. This red, scaly, itchy rash is more common in young infants and those who have a personal or family history of allergy.

Common triggers include aeroallergens like cat dander or house dust, overheating or sweating, and contact with irritants like wool or soaps. In older individuals, emotional stress can cause a flare-up. For some patients, usually children, certain foods can also trigger eczema. Skin staph infections can cause a flare-up in children as well. Eczema patients usually have very dry skin and “allergic shiners” (an extra crease, called a Dennie’s line, across their lower eyelids). They are also more at risk for other skin infections.

Preventing the eczema itch is the main goal of treatment. Do not scratch or rub your rash. Applying cold compresses and creams or ointments is helpful. Also remove all irritants that aggravate your condition from your environment. If a food is identified as the cause, it must be eliminated from your diet.

Topical corticosteroid cream medications and topical calcineurin inhibitors are most effective in treating the rash. Antihistamines are often recommended to help relieve the itchiness. In severe cases, oral corticosteroids are also prescribed. If a skin staph infection is suspected to be a trigger for your eczema flare-up, antibiotics are often recommended.