Patch Test: Why Is It Important?

Here at Lorde and Belle, we are dedicated to using the best ingredients when we formulate our skincare products to give you healthy skin. All our products are based in science and dermatologically tested. However, people are different; they can be allergic to all kind of materials and ingredients. This is why patch testing a product before using it, is nonnegotiable.

What is patch testing?
A patch test is an easy test you can do to see if a specific product may cause an unwanted reaction on your skin. It is different from an allergy test, which is performed by a doctor. Patch testing involves applying the same amount of product you would apply on your face, on a small patch of skin that’s usually on the underside of your arm or the bend of your elbow. If that area gets itchy or irritated, that indicates that you can have a reaction to that product and it’s better to avoid it.

This type of test can be done for any cosmetic product like moisturizers, serums, makeup or even hair dye. American Academy of Dermatology recommends the following steps for patch testing:

1. On cleansed and dry skin, apply the same amount you would normally use on a spot where the product won’t be rubbed or washed away, at least for 24 hours before you start using it on your skin.
2. Leave the products on your skin as long as you would normally do. If it’s a cleanser, leave it about 5 minutes.
3. If you don’t experience red, itchy, or swollen skin, you can start using it on your face. However, if you experience a reaction, wash the spot immediately and apply a cool compress or petroleum jelly to relieve your skin, if needed.

There are two types of irritation that can happen after a patch test. The first one is a fast response to an irritating ingredient, it can happen within minutes or hours and it’s called irritant contact dermatitis. The other on in more severe, it’s called allergic contact dermatitis. It is a slow response to an irritating ingredient, it happens after about four days after developing.

There are some common known ingredients that may cause irritation to the skin like retinoids, exfoliating acids, alcohol, or products like soaps, cleansers, hair dye etc. Some other ingredients may cause allergic contact dermatitis like lanolin oil, methylchloroisothiazolinone, fragrance etc. and the best thing is to absolutely avoid them. Keep in mind that for certain products, irritation is a common and expected side effect, like retinoids or acids. In this case, you have to follow a
specific plan on how to slowly incorporate them in your skincare regimen.