Facial fillers are treatments used to restore lost volume or enhance certain areas of the face. As we age, certain parts of the face can lose volume, or some individuals may want a more voluminous appearance. In cases where hyaluronic acid-based fillers, semi-permanent, or permanent fillers are used, certain sensitive areas of the face—particularly under the eyes—carry a higher risk of complications. This is primarily due to the disruption of lymphatic drainage in those regions or the tendency of even temporary fillers to persist over time.