Definition
Allergic contact dermatitis occurs when the body is exposed to a compound that causes an allergic reaction. When this happens, the skin's immune system reacts to fight the compound, which is perceived to be harmful to the body, even though it is harmless. Dermatitis is defined as an inflammation of the skin, so contact dermatitis refers to skin inflammation caused by contact between the skin and a substance. The substance that provokes an allergic reaction can vary from individual to individual. In most cases, allergic contact dermatitis is caused by jewelry or other metals in everyday objects.
There are two types of contact dermatitis: allergic and irritant. Irritant contact dermatitis is skin inflammation caused by chemicals that cause skin inflammation or irritation, such as pesticides, dish soap, cement, detergents, and others. It occurs in all people exposed to such substances.
In allergic contact dermatitis, not everyone experiences an inflammatory skin reaction after exposure to the same substance. Exposure to the substance that triggers the allergic reaction will trigger an excessive immune reaction and an increase in white blood cells, at the site of contact of the substance with the skin.
Causes
Allergic contact dermatitis occurs after repeated exposure to allergy-triggering compounds. When the skin first comes into contact with the substance, it becomes sensitized, and the immune system perceives it as an allergy-inducing compound. On second exposure to the same substance, an overactive immune system is triggered, and inflammation occurs. Symptoms of inflammation appear within 4-24 hours after exposure. The skin may become sensitized on first exposure or after multiple exposures, which varies with each individual.
Substances that often cause allergic contact dermatitis include:
- Nickel, commonly found in jewelry
- Other metals such as cobalt, chromium, mercury, gold
- Medicines, such as antibiotic creams, antiseptics, non-steroidal painkillers, and sunscreen
- Balsam
- Formaldehyde is used as a preservative and disinfectant
- Personal care products, such as deodorants, soaps, hair color, cosmetics, and nail polish
- Plants, such as poison ivy and mangoes that contain allergenic substances like urishiol
- Pollen
- Insecticides
- Products that cause skin reactions when you are exposed to sunlight (photoallergic contact dermatitis), such as sunscreen or other medications
- Fragrances in soaps, detergents, etc.
- Rubber materials, such as latex gloves, condoms, catheters and balloons
Children may develop allergic contact dermatitis after using diapers, wet wipes, sunscreen, or clothing with certain dyes.
Risk factor
Specific jobs and hobbies can increase your risk of developing allergic contact dermatitis, including:
- Healthcare workers
- Building and construction workers
- Hairdressers and makeup artists
- Mechanics
- Divers, due to exposure to rubber in goggles
- Chefs or people who work with food
Symptoms
Symptoms of allergic contact dermatitis include:
- Itching is the main symptom of allergic contact dermatitis, more severe than pain
- Reddish rash on the skin
- Dry and crusty skin
- Bumpy with a small cluster of pimples or blisters
- Painful with a burning or stinging sensation
- Swollen, hive-like or elevated from the skin surrounding it
- History of skin contact with allergenic ingredients
Symptoms of allergic contact dermatitis on the skin do not appear immediately after exposure, but about 4-48 hours after exposure. The timing of these symptoms varies from person to person, but they are not as immediate as in irritant contact dermatitis.
Diagnosis
The doctor will diagnose allergic contact dermatitis based on the symptoms and findings on the skin. The doctor must ask questions about occupation, hobbies, homework, travel history, clothing materials used, cosmetics, and usual activities. In some cases, the location and shape of the inflammation on the skin are distinctive enough for the doctor to determine the diagnosis with more certainty. For example, in cases of allergic contact dermatitis caused by necklaces, there will be inflammation around the neck.
If the diagnosis cannot be made with certainty, your doctor will perform a patch test to see which substances your body perceives as compounds that trigger allergic reactions. This is done by applying a small amount of a substance that often triggers allergies to your skin for 2-3 days. After that, your doctor will ask you to come back to see how your skin reacts to these substances.
Management
Your doctor will treat the dermatitis according to its severity. Certain medications are not necessary in mild conditions.
Regular skin care can help with healing, such as using moisturizers and washing the affected areas exposed to allergens. Moisturizers can help keep your skin moisturized. Moist skin regenerates more easily, so wounds can heal quickly. Moisturized skin is also relatively more protected from exposure to allergy-triggering compounds and less prone to inflammation.
If the itching and skin symptoms persist, your doctor may prescribe some of the following such as:
- Steroid cream relieves the symptoms of dermatitis on the skin. The cream can be applied 1 to 2 times daily for 2 weeks depending on the doctor's instructions. Do not use or buy this cream without a prescription.
- Oral medicine such as:
- Corticosteroids to relieve inflammation
- Antihistamines to relieve itching
- Antibiotics if there is a bacterial infection on the skin
The rash and inflammation on the skin due to allergic contact dermatitis will disappear within 2-4 weeks.
Treatment at Home
- As much as possible recognize and avoid substances or compounds that trigger allergic reactions in the body
- Use anti-itch cream on the skin exposed to allergy-triggering substances
- Use cold compresses on the redness or rash of the skin
- Do not scratch the redness of the skin
- Protect your hands by washing your hands, using moisturizers, and choosing gloves that do not cause allergic reactions
- If the skin comes into contact with an allergy-triggering substance, immediately wash the contracted skin surface with soap and dry it off.
Complications
Complications of allergic contact dermatitis include:
- Itching that interferes with daily activities
- Discoloration of frequently exposed skin to become darker
- Secondary bacterial skin infection
Prevention
Preventive measures you can take to avoid allergic contact dermatitis include:
- Avoiding known allergens. You can get tested to find out which substances you are allergic to.
- Wash your hand and skin immediately after coming into contact with a known allergen or irritant using soap and warm water
- Use personal protective equipment if you have to be exposed to certain allergy triggers
When to see a doctor?
See your doctor if you experience:
- An itchy skin rash that interferes with sleep or work
- Have a sudden rash that is painful and spreading
- Your skin rash does not improve within 3 weeks
Seek help immediately if you experience:
- Infection of the skin, characterized by pus and fever
- Your lungs, eyes and airway are painful from inhaling allergens
- Swelling of the lips and mouth after exposure to certain substances
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- dr Hanifa Rahma
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