Some things to consider: According to the Environmental Working Group, women use 12 personal care items every day on average, totaling 168 toxic components (EWG). Spending money on a new skin-care product is exciting—until you use one that causes your skin to become irritated, red, or itching.
After switching to a new skin-care product, if you realize that your skin is irritated for no apparent reason, the product’s ingredients may be to fault.
Because of this, skin care professionals and companies alike advise conducting a patch test before include a new formula in your regimen.
A Patch Test: What Is It?
According to Nava Greenfield, MD, a board-certified dermatologist of Schweiger Dermatology Group in New York City, a patch test is, broadly speaking, the application of a product or substance to a small area of skin and observation of the skin’s response.
You can find out how your skin could respond to a new product by patch-testing it before you use it liberally and risk negative effects.
What might that response entail? According to Dr. Joshua Zeichner, the director of cosmetic and clinical research at Mount Sinai Hospital in New York City, a minor reaction could be a small amount of redness. On the most severe end, you might get what he describes as a serious condition, such as a “scaly itchy rash that may require a prescription medicine to settle it down.”
So how exactly do you conduct a test at home? And when should you seek the advice of experts instead? With the help of board-certified dermatologists, we’ve broken down everything you need to know about skin-care patch testing in this article.
What Is the Purpose of a Patch Test?
To determine whether a product or component may cause your skin to react unfavorably, a patch test is conducted. It will assist you in determining whether to add that product to your skin care routine going forward or whether you ought to stay away from it totally.
“A reaction could indicate a sensitivity to the product or substance, or a contact allergy, “Dr. Greenfield notes. According to the U.S. Food and Drug Administration, symptoms of an allergic reaction include a rash, hives, and discoloration (redness on lighter skin tones or dark brown, purple, or gray on darker skin tones) (FDA). It’s crucial to remember that sensitivity can also provide findings that appear to be comparable.
In response to a new skin care product, you may experience either irritating contact dermatitis or allergic contact dermatitis, according to Dr. Zeichner.
Because you’re employing a harsh substance that your skin chemistry can’t handle, the former induces a reaction, he says. He contrasts this with allergic contact dermatitis, which occurs when “a product constituent activates an immunological response.”
While a less thorough at-home test can only give you a general notion of what you could be allergic to, a professional patch test can identify allergens. On it, however, more later.
What Is the Difference Between At-Home and In-Office Patch Testing?
Patch tests can be performed either at home or in a dermatologist’s office. However, these are very dissimilar experiences.
Home patch testing “can determine if you’re sensitive to a substance, but it doesn’t necessarily tell you if it’s an allergy or an irritant,” says Zeichner. Professional patch testing, on the other hand, “can tell you if it’s an allergy or an irritation.”
He says, “It also doesn’t tell you which chemical you are directly allergic to. Although it’s not certain, “if you’re using a product with a harsh active ingredient, you can likely ascribe the reaction to that active ingredient.”
Patch testing done professionally is a completely different game. According to Zeichner, the technique involves applying upwards of 80 sticky patches or more on the back of the subject. “Each patch includes a single active ingredient, such as a fragrance, pigment, or preservative, that is frequently linked to an allergic reaction in the skin.
He says, “These patches are left in place for 48 hours, so no shower while they’re on.” The dermatologist removes them when you return to the office and examines your skin to determine whether a reaction is forming.
The decision? A solid standard practice to avoid an unwanted reaction is to conduct an at-home patch test when you acquire new skin care. But in circumstances when allergic contact dermatitis is suspected, you’ll still require a professional process.
How Should You Patch Test Products?
As annoying as it may sound, Zeichner advises patch-testing any new skin-care item before incorporating it into your routine.
You’re impatient. He suggests at the very least performing a patch test before utilizing products with active components, noting that retinol, vitamin C, and exfoliating acids are the three most likely to cause irritation.
In terms of products you can probably avoid patch testing, the expert advises that moderate moisturizers (formulas without active chemicals or aroma) “should be perfectly fine.”
The lesson? Patch testing is recommended for all products, especially those having abrasive active components. You and your skin are better off being safe than sorry, after all.
How to Conduct a Patch Test for Skin Care
The procedures listed below, according to Zeichner, should be used to conduct an at-home patch test.
- Use your regular cleanser to thoroughly clean the skin region where you will apply the product, then pat the area dry.
- Right in front of your ear, use a product the size of a half-pea. (The expert prefers clients to patch test a product on their intended use’s facial skin.)
- If you observe any signs of a negative reaction (such redness, itching, or irritation) during the course of the next 24 hours, keep an eye on this region of skin and wash it with a mild cleanser before applying a skin-protecting component (opt for a fragrance-free cream or lotion, as these are less likely to irritate the skin, per the American Academy of Dermatology Association).
You’re fine if your skin appears to be in decent condition.
Zeichner advises a second round of patch testing if your only symptom is a slight amount of redness and you’re still keen to try the product. He advises layering moisturizer over it the following time “to see if it’s better tolerated that way.”
If this isn’t the first time you’ve seen a rash and you’re having trouble determining the cause, it may be time to see a dermatologist. To determine what external element is generating the reaction, they can decide that it is necessary to arrange a professional patch test.
Summary
Patch testing at home is a proactive measure to guard against an unpleasant reaction to novel skin care products. A more thorough patch test conducted by a dermatologist may be necessary to identify the chemicals to which you are sensitive or allergic if you frequently react to new skin-care compounds or if your dermatologist suspects you have an allergy to one of them.
