Allergic contact dermatitis is an irritation of the skin caused by a direct contact with a foreign substance termed as primary irritants.
Symptoms can include a rash, blisters, itching and burning. These symptoms can appear within minutes of exposure and fade away within minutes to hours or may take several days to weeks to heal.
Many substances can cause such reactions, including cosmetics, hair dye, fragrances, laundry detergents, nickel and latex.
Atopic dermatitis or eczema is a chronic skin condition where patches of skin become inflamed, red, itchy and may look very dry and may ooze when scratched. It is common in children but can occur at any age.
Eczema may be caused by a combination of genetic, environmental and immune system factors. Although allergies may aggravate eczema, they are not the cause. In fact, recent evidence suggests the opposite may be true, eczema may cause allergies! Most cases of atopic eczema appear to be genetic, reflecting an inherited defect in skin barrier function, leading to increased water loss and resultant inflammatory changes. There is no cure for eczema, but available treatments focus on healing damaged skin and minimizing symptoms. Many children will “outgrow” eczema over time, and recent studies suggest eczema can even be prevented in higher-risk infants.
Urticaria, commonly known as hives, are red, very itchy swellings that usually occur rapidly and eventually disappear with or without treatments.
Hives can vary in size and occur in groups or any part of the skin, before fading and appearing on another area of the body.
Hives can be a sign of an allergic reaction, however there are many other common causes of hives, including viral infections, some medications such as codeine and morphine, and physical triggers, such as heat, cold, pressure, vibration, and scratching.
Chronic urticaria, hives which come and go for months or years, are not a sign of an external allergy, but are instead an autoimmune phenomenon. They are usually controllable with safe and effective medications, and allergists at Snö Asthma & Allergy have a great deal of experience managing acute and chronic hives.