L'Oreal Paris Revitalift Pure Hyaluronic Acid Serum, A dermatologist validated, highly-concentrated, anti-aging plumping hyaluronic acid serum that immediately hydrates and fills wrinkles in 2 weeks. Our Pure Hyaluronic Acid formula is infused with Vitamin C, a vital antioxidant known to boost skin's radiance. What Does Hyaluronic Acid Do? Hyaluronic Acid is a potent hydration-attracting molecule naturally found in the skin, but we lose it as we age which leads to lack of firmness and dryness. Hyaluronic Acid is a safe ingredient used by dermatologists for its intensely hydrating and replumping properties.