Lip fillers are cosmetic injectables used to enhance the volume and shape of the lips. They typically contain substances like hyaluronic acid, which is a naturally occurring substance in the body. The procedure is minimally invasive and can be done in a doctor's office, usually taking about 15 to 30 minutes. The effects of lip fillers can last from six months to a year, depending on the type used and individual factors. Common side effects may include swelling, bruising, or tenderness at the injection site. It's important to consult with a qualified professional to discuss goals and potential risks before undergoing the treatment.