These natural fillers are non-toxic, biodegradable gels, made of non-animal derived, hyaluronic acid. Fillers can be effectively used to enhance lips, by increasing fullness or reducing surrounding lip lines. They can also be used to shape facial contours such as cheekbones. Hollows under the eyes, marionette and deep smile lines, as well as deep frown lines between the brows can also be reduced. During a treatment, the filler is injected in the target area and binds with water in the tissue. The effects last several months, until the filler is fully absorbed by the body and disappears.