You should always test any skin care product on a small area of your skin before using it on a wider area of your skin. Patch testing (sometimes called spot testing) allows for safe, controlled testing of skin care products since it involves testing products on small areas of skin rather than applying them to the entire face. This way, you can ensure you’re not allergic to a particular product before you risk experiencing that allergy in a bigger area.
Patch testing is a test intended to determine whether you can safely apply certain products to your skin. It is most commonly done on people with sensitive skin or allergies, but it’s helpful for everyone to know how to do it.
How to Patch-Test a Product
Patch testing is a quick way to assess your skin’s sensitivity to substances. Patch testing is useful for assessing skin irritancy, allergic reactions, sensitivity to cosmetics, and long-term skin monitoring.
Use a Clear Patch of Skin
It’s a simple, inexpensive procedure that doesn’t require a doctor’s visit. Patch testing is performed using a clear patch of skin, usually the inside of your forearm, and is typically used for cosmetics, fragrances, and skincare products.
Wash the Area First
You may have read before that you should patch-test any new product you buy so that you can ensure that it does not cause an adverse reaction. To patch-test, a product, first, wash your skin thoroughly with soap and water. Before you even touch the product:
- Cleanse the area and apply some petroleum jelly or moisturizer. This will help avoid getting any product on your face that might cause irritation and redness.
- Use a mild soap that will not irritate the skin.
- Dry the area thoroughly with a clean towel.
- Never use a rough towel.
Apply a Small Amount to the skin
Prior to applying any product to your skin, you should read the label and the ingredients list carefully. Then patch-test the small area of chosen skin that you have prepared first (such as the inside of the elbow, the back of the neck, or the inner wrist).
Wait 24 Hours
Patch-testing is especially helpful for individuals who may have a sensitivity to a product. You can patch-test a product 24 hours before using it on your face, as it takes that long for your skin to heal fully. The simplest way to discover if a product is safe for you is to test it on your wrist. Patch testing involves applying a small amount of a product to your skin for 24 hours and then observing any reaction you may have. Common results include red bumps, rashes, and irritation.
Common Allergens in Cosmetics
The patch is applied for 24 hours and then removed and inspected. Upon removal, the dermatologist or dermal therapist will look for reactions such as itchiness, swelling, or redness. A red ring around the patch indicates that your skin is allergic to the suspected ingredient. You can then discuss possible alternatives with the doctor or therapist. This can determine if the product is harmful, and patch-testers use this method to check for a lot of the most common allergens, such as nickel, preservatives, and fragrances.
Read the ingredients list carefully: it’s better to invest in a product you know is safe than risk a reaction. If there’s anything you’re unsure of, a patch test can determine exactly which products your skin can tolerate.
Patch tests are simple to do and, on their own, won’t cause a reaction. But, if the patch test shows you’ve reacted to an ingredient, it’s ample opportunity to wean yourself off that product.