Restylane is the trade name for a range of injectable fillers with a specific formulation of non-animal sourced hyaluronic acid (HA). Restylane is most commonly used for lip enhancement (volume and contouring). It is used to diminish wrinkles and aging lines of the face such as the nasolabial folds (nose to mouth lines), melomental folds (sad mouth corners), "crow's feet" and forehead wrinkles (frown lines). It may also be used for filling aging-related facial hollows and "orbital troughs" (under and around the eyes), as well as for cheek volume and contouring of the chin, forehead and nose. After the initial treatment, follow-up sessions are normally recommended around every 6 to 12 months depending on the individual and the treatment.