Injection and Infusion Coding: What You NEED to Know! Not all injections are created equal and in the CPT Medicine section, the difference between an IV infusion, an IM injection, CYANOCOBALAMIN J Code: J3420 Cost and Price CYANOCOBALAMIN INJECTION, USP 30000 mcg 30 mL (1000 mcg mL) 30 mL VIAL When coding for trigger point injections, the documentation must include the site of the injection, the total number of injections and the number of muscles involved. There are two CPT codes