You’ve just bought a new skincare product and you’re excited to see how it might transform your look. Instead, you end up with red, itchy or swollen patches because one of the ingredients causes an allergic reaction.
The best way to avoid this problem while trying something new is to test it on several small areas of your skin first to determine whether it’s likely to irritate you, according to board-certified dermatologists from the American Academy of Dermatology.
“There are more than 15,000 allergens that can cause allergic contact dermatitis, and skincare products are a common cause,” Dr. Bruce Brod says. “Even products labeled ‘hypoallergenic’, ‘natural’ or ‘clean’ can cause a skin reaction, so it’s helpful to test skincare products before using them as you would normally.”
What is contact dermatitis?
Contact dermatitis happens when the skin becomes irritated or inflamed after coming in contact with a substance that triggers an allergic reaction.
Contact dermatitis has some of the same symptoms in common as the six other types of eczema. However, unlike atopic dermatitis, which is the most common and difficult-to-treat form of eczema, it doesn’t run in families and isn’t linked to other allergic conditions such as hay fever or asthma.
According to the National Eczema Association, there are two main types of contact dermatitis:
- Irritant contact dermatitis, which accounts for 80% of all contact dermatitis, doesn’t involve an allergic reaction by the immune system. Instead, it happens when skin cells are damaged by exposure to irritating substances, such as solvents, detergents, soaps, bleach or nickel-containing jewelry. Makeup, hair dye, nickel-containing scissors, belt buckles or clothes with metal snaps or zippers can also trigger reactions — as can over-washing hands with hot water and soap and wearing scratchy wool.
- Allergic contact dermatitis is a delayed allergic reaction that appears as a rash a day or two after the skin is exposed to an allergen. A common example is poison ivy. After exposure, the body generates a robust inflammatory reaction to the oils in the plant leading to an itchy rash within one to two days. Fragrances, nickel and the preservative thimerosal, which is found in some topical antibiotics, are also common causes of allergic contact dermatitis.
How to test skincare products
To test a skincare product, Brod recommends applying the product to a quarter-sized test spot twice daily for seven to 10 days. Choose an area where it won’t be easily rubbed or washed away, such as