Skin allergy is a common disease that results from the interaction of the body with an allergen. The immune system considers the allergen as dangerous which leads to the release of antibodies. This manifests as red, itchy or scaly rashes on the skin.
There are many kinds of allergen that can trigger the skin reaction. These allergens can be inhaled, ingested or come into contact with the skin. Some common allergens include nickel which is found in jewelry, belt buckles and zippers, fragrances found in perfumes and lotions, household products, antibiotic creams, latex which is the rubber found in gloves and balloons, and plants such as poison ivy and poison oak. The skin allergy can manifest within a few minutes to a day after being in contact with the allergen.
Types of skin allergies:
- Contact dermatitis occurs when the skin comes in contact with an allergen or irritant. The skin in contact can become red, itchy, and painful, and form rashes. The symptoms appear within 12 hours to 3 days and resolve after 2 to 4 weeks even with proper treatment.
- Hives present as raised, itchy bumps that can be triggered by contact dermatitis or an allergic reaction to other substances. The bumps appear almost immediately and fade within a few hours to days.
- Eczema is a chronic skin condition that can be triggered by animal fur, cleaning products and dust. It manifests as itchy, red and dry skin.
A doctor can diagnose skin allergies through the patient’s medical history and physical exam. A skin test can be done by placing samples of possible allergens on the patient’s back and leaving it for 2 days. A skin reaction can confirm a substance as an allergen for the patient. Another method is skin pricking wherein the skin under a drop of liquid allergen is pricked with a needle. The patient is allergic to the substance if a red, itchy bump appears within 15 minutes of pricking.
The presentation of skin allergy varies from one type to another. Common symptoms on the skin include:
Red, raised bumps
Dry or scaly patches
An anaphylactic shock is a severe allergic reaction that rarely occurs. This develops within minutes of exposure to the allergen and involves the whole body. Additional symptoms include:
Swelling of throat and mouth
Difficulty in breathing
Blue lips or skin
Loss of consciousness
Commonly Prescribed Drugs
- Antihistamines are the most commonly prescribed drugs for allergies. These can be given before or during an allergic reaction. Diphenhydramine is a widely used antihistamine that resolves hives, skin rash, itching and other allergic symptoms.
- Topical emollients moisturize the skin by reducing water loss and forming a protective barrier over it. This is used on dry or scaly skin. Ointments are used for very dry skin for its high oil content while creams and lotions work for less dry, but inflamed skin. Do not rub in the emollient. Lightly smooth it out in the direction of hair growth.
- Calamine lotion is useful in soothing and protecting irritated skin. Shake the container well before application. Use a cotton or soft cloth for easier application. This is for external application only.
- Corticosteroids are prescribed to reduce skin inflammation and itchiness. These can be given as creams or tablets. Side effects: mild burning or stinging sensation, thinning of skin, skin color changes, reduced growth rate in children, hypertension, osteoporosis, diabetes.