Global · UPDATED SEPTEMBER 3, 2026
How to patch test and introduce new skincare
Reduce guesswork when trying a new serum, cream or active ingredient.
Test one new product at a time
When several products start together, a reaction is difficult to trace. Keep the rest of your routine familiar and introduce one item first. Check the label for product-specific directions because rinse-off products and leave-on treatments are used differently.
Use a small, limited area
Apply a small amount to a discreet area of intact skin and repeat according to the label before broader use. Patch testing cannot predict every delayed reaction or breakout, but it can reveal obvious discomfort before the product goes across the whole face.
Watch for more than one night
Immediate burning, swelling or hives call for stopping the product. Dryness, persistent redness and clusters of irritation can appear later. Avoid assuming that painful irritation is a necessary purge, especially when the product is not designed to increase cell turnover.
Know when professional help matters
Cosmetic guidance cannot diagnose an allergy, eczema, acne or another medical condition. Seek qualified medical advice for severe swelling, breathing difficulty, blistering, eye involvement or symptoms that persist after stopping the product.