An intra-articular injection is a term used to describe a shot delivered directly into a joint with the primary aim of relieving pain. Corticosteroids (steroids) were the first substances used for this purpose. Other types of drug are now commonly used including local anesthetics, hyaluronic acid, and even Botox.An intra-articular injection is typically given when the pain has not responded to more conservative treatments including pain relievers, oral anti-inflammatory drugs, and physical therapy.