The Ordinary Niacinamide 10% + Zinc 1% is a high-strength vitamin and mineral serum formulated to reduce skin blemishes and congestion. This water-based formula combines 10% pure niacinamide (vitamin B3) with 1% zinc PCA to improve skin barrier function, smoothness and radiance. This serum should not be used simultaneously with vitamin C products - they should be applied at different times of day for optimal effectiveness. While this formula helps with blemishes and skin tone, it is not specifically an acne treatment. The product comes in a 60ml bottle with a dropper applicator for precise dispensing. A patch test is recommended before first use to check for any sensitivity.