Sunday Riley A+ High-Dose Retinoid Serum combines 5% retinoid ester blend, 1% liposomal-encapsulated retinol blend, and 0.5% blue-green algae with natural, retinoid-alternative activity, this serum fights the signs of aging and improves the look of congested and UV damaged skin. Encapsulated CoQ10 helps to improve the appearance of aging or damaged skin, while rare, Hawaiian white honey, bisabolol, cactus extract, and ginger balance and soothe the skin for the appearance of a calmer, even-toned complexion.