- Formulated to enhance the definition of curls and waves, this shampoo features Acanthus extract and Evening Primrose oil to gently cleanse while offering frizz control and silky-soft texture without weighing hair down. Gentle shampoo for enhancing curls and waves. Offers frizz control, volume and definition. Acanthus extract promotes curl and wave shape. Evening Primrose oil helps protect hair from humidity. Indigenous to the area surrounding the Mediterranean, the protein-rich extract from the leaves of this ornamental plant forms a weightless coating on each hair to help add shape, volume and definition to curls. Evening Primrose oil: With a high concentration of omega-6 fatty acids, this flower-derived oil promotes smooth, defined curls and helps reduce humidity-induced frizz. Leaves hair soft, smooth, bouncy and shiny. Apply to wet hair, work into a rich lather and rinse thoroughly.