Skin Allergies and Contact Dermatitis: The Basics
How do I Find Out What I’m Allergic To?
Your doctor can check to see what you’re reacting to, but finding the exact cause may be hard. Skin tests can only show what you're sensitive to. They can't tell what touched your skin in a specific spot on a specific day.
Doctors often use the TRUE test. It's a pre-packaged set of three panels that your doctor will stick to your back. Each is smaller than a dollar bill and has 12 patches with samples of possible allergens. You wear them for 2 days. Then the doctor takes them off to see if you've had any reactions. You might need to come back a few more times, since some reactions could show up as many as 10 days later.
You might be allergic to something that isn’t in the standard TRUE test. To figure that out, your doctor may do more patch testing. He’ll choose substances you might contact in your work, home, or hobbies.
If you have a mild reaction in any patch test, you might need to follow up with a ROAT test. It works a lot like the TRUE test, but you do it yourself. Put the suspected allergen, say, sunscreen, on your skin during the day in the same spot over several days. This can help confirm or rule out your sensitivity.
The dimethylglyoxime test looks for metal objects that have enough nickel to cause a reaction. Your doctor can test things in the office, or you can buy a kit to test jewelry and other items yourself.
How Is Contact Dermatitis Treated?
The best method is prevention. Find out what causes your rash and avoid it. You may need to wear gloves to protect your skin.
When you do have a reaction, try to ease the symptoms and prevent an infection. Don't scratch, even though that's a hard urge to resist. Over-the-counter products and home remedies can help relieve the itching and stop the swelling. Try these: