Should I use the 10% Niacinamide Booster, the CLINICAL Niacinamide 20% Treatment or both? For most, using one or the other is all that is needed. For those with milder pore concerns or who haven’t tried a highly concentrated niacinamide product, 10% is best. For those with especially stubborn concerns, 20% is best. If the severity of your skin concerns varies over your entire face, we suggest experimenting with both products. How does 10% Niacinamide Booster visibly tighten enlarged pores? Niacinamide has research showing improvement in skin’s firmness and normal pore function. As the skin ages, the pore wall is damaged, and stretches as skin’s supportive structure depletes, resulting in enlarged pores that may or may not become clogged. Niacinamide restores some normal pore function, visibly firms and smooths which improve skin’s texture. Are there any products or ingredients I shouldn’t mix with 10% Niacinamide Booster? You can layer this niacinamide booster with any product or ingredient, as tolerated. If preferred, mix a few drops into any non-SPF product including serums, moisturizers or other boosters. Is 10% Niacinamide Booster suitable for sensitive skin? While niacinamide is a potent ingredient, we’ve formulated this booster with additional skin-soothing ingredients like allantoin, boerhavia diffusa root and licorice extract, so many people with sensitive skin have used it successfully with beautiful results. If you are concerned, patch test it first by applying it in a small area or mix it in into any non-SPF product for a few days to see how your skin responds. What does a niacinamide booster do? This niacinamide booster helps skin appear renewed and clarified, visibly fades post-blemish marks and minimizes enlarged pores, all while preserving skin’s barrier. How to use Paula’s Choice Niacinamide Booster? You can experiment with using this versatile niacinamide booster in various ways. Dispense a few drops into your palm and apply directly to skin or mix its water-light texture into other non-SPF products. Can I use niacinamide and vitamin C together? Yes, niacinamide and vitamin C can be used together. In fact, this booster contains 2% ascorbyl glucoside, a form of vitamin C that provides brilliant results for fading the look of sun-induced discolorations when combined with niacinamide. Learn more about using niacinamide and vitamin C together.