Botulinum toxin improves the appearance of wrinkles by temporarily paralyzing the muscle it is injected into, thereby preventing the contraction of that muscle. This prevents the overlaying skin from wrinkling and developing imprinted lines over time. When our face animates and moves, these wrinkled areas (most commonly between the eyebrows, across the forehead, and on the sides of the eyes) eventually create imprinted wrinkles, which can appear even during rest. Neuromodulators can be injected into the muscles in these areas to prevent expressions that form these lines.