Belotero Balance (Merz), an injectable hyaluronic acid dermal filler, has been approved by the FDA for temporary correction of moderate-to-severe facial wrinkles and folds. Several other hyaluronic acid products are also available for this indication (e.g., Restylane, Perlane, Juvéderm). They have supplanted bovine collagen products, which persist for a shorter time and cause more allergic reactions.