Before using any new cosmetic product, it is recommended to perform a sensitivity test. Apply a small amount of the product to a discreet area such as the inside of the wrist or behind the ear, and wait 24 hours to see if there is any adverse reaction. If you are introducing more than one new product into your skincare routine, it is best to test each one separately to clearly identify any possible sensitivity. Always follow the specific instructions on the packaging for each product.