If you are concerned about a reaction to a new skincare product, here is a simple test routine to use for a week or so.
Choose a quarter-sized spot on your skin where the product won’t be rubbed or washed away, such as the underside of your arm or the bend of your elbow. Use the normal amount and thickness you would use as if you were applying the product regularly.
Leave the product on your skin for as long as you would normally. If you’re testing something that you would usually wash off, like a cleanser, keep it on your skin for five minutes or as long as the instructions say.
If after seven to ten days you don’t have a skin reaction, such as red, itchy, or swollen skin, it seems safe to say you can go ahead and use the product.
Keep in mind that some ingredients, such as retinol and glycolic acid, can irritate your skin, particularly if your skin is sensitive. This is normal and temporary.
If you develop a skin reaction, gently wash the product off as soon as possible, and don’t use it again. Apply a cool compress or petroleum jelly to relieve your skin, if needed. If your reaction to a product is severe and not relieved with cool compresses or petroleum jelly, you may need to see a dermatologist to help manage your symptoms.