Yes. Always patch test new products. It's especially important for anyone with sensitive or problem skin. It is possible to experience an adverse reaction to a product simply because your skin doesn't like a specific ingredient or doesn't respond well to the way a product is formulated. You should patch test two different patches of skin. First test somewhere hidden and then somewhere close to the area where the product will be applied once you've passed the patch test. For example, if you’re testing your face, a nice location is the side of your neck. Also test behind your knee, on your belly or your upper arms. Apply a tiny amount to the test area. Reactions will typically occur immediately or within a few minutes. If you don’t have a reaction, then is reasonable to use the soap as you wish.
Should I patch test prior to use?
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