How to Patch Test a Skincare Product the Right Way.

by | Last updated Apr 4, 2021 | 33 comments

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This is such an important skincare topic that’s all too often avoided. Patch testing properly can prevent severe allergic reactions and go a long way in clearing acne, particularly for those suffering from “acne-cosmetica,” that is, comedones, pustules or papules caused by using products that are incompatible with your skin. (1)

Remember to patch-test absolutely everything before incorporating it into your skincare routine or going full-faced. I cannot stress this enough.  Skincare requires patience: this isn’t a sprint but a marathon.

Trying to add more things to get faster results usually impedes, rather than helps progress. And as you can see, I’ve learned a thing or two about patch-testing…. it only took 8 year worth of products, my poor wallet, and dozens of breakouts to learn my lesson. -___-

What is patch testing?

Patch testing is a method of testing a new product to see if it will work for your skin. This test is often ignored, and can result in pretty severe acne or allergic reactions.

malassezia folliculitis patch testing

Believe it or not, a lot of the problems you see above were simply caused by using the wrong things on my skin. If you have adult acne, there’s a very good chance your breakouts are product related. If you suspect this might be the case, stop using everything for at least two weeks and see if things subside.

Scary I know, but had I never took that leap of faith I wouldn’t have successfully cured my acne. It was only after dropping everything from my skincare routine and introducing products back in slowly, that I was able to determine what my skin likes, and what it doesn’t. Without further ado, let’s go into the methodology.

How to patch test.

There are three different things to test for:

1. Allergic reactions.

Apply the product in question behind your ear.

2. Irritation.

Apply the product in question where you’re most sensitive. This will vary from person to person, for me it’s the corners of my nose and chin.

3. Comedogenicity (how pore-clogging something is).

Apply the product you’re testing to the area you experience the most breakouts and clogged pores. This will also vary from person to person. For me, it’s my chin and the space between my eyebrows.

How long do I need to patch-test a product?

Once again, this varies from person to person. For example, I breakout very quickly (it’s ridiculous, really), so I’ll know if a product is giving me problems within 24 hours. Others (like my sister) require several days of patch testing to finally notice something is going astray.

Just remember to apply the product on enough surface area that it allows you to notice a problem should one arise, but small enough that it won’t be detrimental if something does go wrong.

Alrightly, that does it skincare-addicts. Have fun with your new products, and PATCH TEST ALL THE THINGS!



Feel free to tell me about your patch testing horror stories in the comments below. Save your fellow skincare-addicts some grief and share this!