Collagen lip injections allow individuals to increase the size of their lips without committing to a permanent result. Collagen lip injections last four to six months, with patients receiving "touch-up" treatments two or three times yearly.

Using collagen lip injections, doctors can increase the size of a patient’s upper or lower lip, or both; some collagen lip injections are used to treat specific areas of the lip, to increase the vermilion, for instance. Collagen lip injections can also help reduce the appearance of wrinkles in the lips as patients age. Because collagen lip injections contain refined bovine collagen, there is a possibility for an allergic reaction. Individuals interested in collagen lip injections are usually screened for allergies to lidocaine and dietary beef, and the doctors administering the collagen lip injections will usually do a spot test to check for allergic reactions. The procedure used for collagen lip injections is considered ambulatory; patients walk in, have the procedure, and go home. Since the collagen lip injections contain lidocaine (an anesthetic), most doctors do not use sedation or a separate anesthetic during collagen lip injections. This means that patients will recover more quickly, and few individuals require pain medication after collagen lip injections, although there is usually some swelling and slight bruising, which subside after a few days. Collagen lip injections are not a permanent solution to thin lips, and most patients receive additional collagen lip injections to maintain the fullness of their lips.