The most common skin allergies include eczema, hives/angioedema and contact dermatitis.
Eczema usually affects the face, elbows and knees. The red, scaly, itchy rash is more common in infants and those who have a history of allergies or asthma. Older children and adults with eczema often experience rashes on the knees or elbows on the backs of hands or on the scalp.
Triggers include allergens, overheating or sweating, emotional stress, food and contact with irritants such as wool, pets or soaps.
Preventing the itch and frequent moisturization is the main treatment goal. Applying cold compresses and topical steroid and calcineurin inhibitor creams are the most effective. Antihistamines are often recommended to help relieve the itchiness. An injectable known as dupixent can also provide long-standing relief.
Hives and Angioedema
Hives are red, itchy, raised areas which may be triggered by food, environmental allergy, latex or drug allergies. Hives can also result from non-allergic sources like rubbing of the skin, cold, heat, physical exertion or exercise, pressure and sunlight. Hives usually go away within a few days. Chronic hives can linger for months to years.
Angioedema is a swelling of the deeper skin layers that sometimes occurs with hives. Angioedema appears on the eyelids, lips, tongue, hands and feet.
Treatment can include antihistamines or in severe cases, steroids. Other tips for symptom relief are cool showers, applying a cool compress or wearing loose/light clothing. Also an injectable known as xolair can provide relief.
Contact dermatitis can be both painful and itchy. It is characterized by an itchy, red, blistered reaction and commonly caused by poison ivy, nickel, perfumes, dyes, latex products or cosmetics. Some ingredients in medications can cause a reaction, most commonly neomycin, an ingredient in antibiotic creams.
Allergic contact dermatitis reactions can happen 24 to 48 hours after contact. Contact dermatitis can be treated by scrubbing the skin with soap and water after exposure and using prescribed antihistamine and cortisone medications. Calamine lotion, oatmeal baths/milk soaks and cool compresses can offer relief.
The diagnosis is made from a detailed history to include: your hobbies, work exposures, cosmetic/fragrance/hair dye/nail polish exposures, exposure to jewelry and other metals as well as physical exam and testing.
The patch test is used for the diagnosis of contact dermatitis. A small amount of diluted test allergens are applied to the skin under a patch of paper tape. The patches are placed on the back and are removed after 48 hours. Skin reactions are looked at and scored at a 48 hour visit and then again after 72 to 96 hours. Testing allows identification of chemicals you are allergic to so that they can be avoided in the future.