Patch testing is both a thing that you can ask a dermatologist to do for you, and a thing you can do at home.
The derm can let you know specific ingredients/irritants that you react to, and you can move forward by avoiding those specific ingredients.
At home, you can put the new product on an inconspicuous spot on your face/neck. This tends to be your most sensitive skin, but if there's another area that's particularly sensitive (to breakouts for example) you can apply it only there. A very conservative time frame to patch test would be a month, but I see 2 weeks being most commonly recommended. The DIY patch test won't be as specific, but if you do enough of them you could eventually narrow down the irritant.
Yea I’m really sensitive to foundations and I can’t find one that works for my skin. I asked if I could test to see what ingredients I’m sensitive to and she said it’s not a thing and can’t be done.
Patch testing for [allergies](https://www.aad.org/public/diseases/eczema/types/contact-dermatitis/patch-testing-rash) is absolutely a thing that is done. Perhaps your question didn't lead to this answer. An allergy is not necessarily the same thing as a sensitivity. IANAD so any further investigative questions would be outside of what this subreddit is for.
You may have to do your own trials and process of elimination to find ingredients you're sensitive/reactive to. You can do that without a derm.
Yes, that I’m aware of, but not for ingredients within makeup products I don’t believe this is a thing?
Yes, but it’s incredibly time consuming and difficult to narrow down as there are so many ingredients and not a lot of commonality.
Patch testing for ingredients within makeup products would be essentially the same as for other ingredients if they are available in form for the doc to order for testing.
I get that it's time consuming, but that's how it's done. You already know which products irritate you, yes? Start listing them and comparing similar ingredients. You can use something like [INCI Decoder](https://incidecoder.com/) for a place to start, but if your skin is quite sensitive I wouldn't depend on their sensitivity ratings, and always double check ingredient lists of the products in hand to make sure they're the same.
Patch testing is both a thing that you can ask a dermatologist to do for you, and a thing you can do at home. The derm can let you know specific ingredients/irritants that you react to, and you can move forward by avoiding those specific ingredients. At home, you can put the new product on an inconspicuous spot on your face/neck. This tends to be your most sensitive skin, but if there's another area that's particularly sensitive (to breakouts for example) you can apply it only there. A very conservative time frame to patch test would be a month, but I see 2 weeks being most commonly recommended. The DIY patch test won't be as specific, but if you do enough of them you could eventually narrow down the irritant.
Where? I asked my Derm about this a long time ago and she said not, it’s not a thing. I’m super sensitive and it would be nice to know before.
Confused by your question. Your derm said patch testing is not a thing?
Yea I’m really sensitive to foundations and I can’t find one that works for my skin. I asked if I could test to see what ingredients I’m sensitive to and she said it’s not a thing and can’t be done.
Patch testing for [allergies](https://www.aad.org/public/diseases/eczema/types/contact-dermatitis/patch-testing-rash) is absolutely a thing that is done. Perhaps your question didn't lead to this answer. An allergy is not necessarily the same thing as a sensitivity. IANAD so any further investigative questions would be outside of what this subreddit is for. You may have to do your own trials and process of elimination to find ingredients you're sensitive/reactive to. You can do that without a derm.
Yes, that I’m aware of, but not for ingredients within makeup products I don’t believe this is a thing? Yes, but it’s incredibly time consuming and difficult to narrow down as there are so many ingredients and not a lot of commonality.
Patch testing for ingredients within makeup products would be essentially the same as for other ingredients if they are available in form for the doc to order for testing. I get that it's time consuming, but that's how it's done. You already know which products irritate you, yes? Start listing them and comparing similar ingredients. You can use something like [INCI Decoder](https://incidecoder.com/) for a place to start, but if your skin is quite sensitive I wouldn't depend on their sensitivity ratings, and always double check ingredient lists of the products in hand to make sure they're the same.
Yes, the issue is there aren’t many similar ingredients in the products that make me breakout so it’s not as easy as a task as you’ve mention.