Syringes are selected based on dose, accuracy and route of administration. Insulin syringes (U 40 U 100) are used for subcutaneous insulin delivery, tuberculin syringes for precise intradermal B12 Injections at Home Safety Guide for Self Administration Infusion For Health How to give insulin shots Stead Family Children's Hospital B12 Shots at Home: How, Where & How Often to Inject Yourself AZ IV Medics How to Give Yourself a B12 Injection ThinWorks How to Read an Insulin Syringe Affinity Whole Health