Restylane is a popular brand of hyaluronic acid (HA) dermal fillers used to smooth wrinkles, add volume, and contour facial features like lips, cheeks, and chin, or improve skin texture. Made from naturally occurring HA, it provides hydration and fullness, offering natural-looking results for up to 18 months, with specific products designed for different areas (e.g., lips, under eyes, deep folds) and sensitivities (some contain lidocaine for comfort).