If you’ve used retinol successfully in the past, you shouldn’t see any issues with the Age-Defying Hyaluronic Acid serum. First-time retinol users may experience irritation, including redness, dryness, and peeling. If you use too high a strength or apply retinol more frequently than you should, you may experience further irritation, like itchiness and scaly patches. We recommend testing the product on the inside of your arm to see if your skin is prone to irritation with retinol.rn