How to choose a needle for insulin injection? Can needles be reused? How to dispose of discarded needles? These are all important issues related to the health of patients. Questions about insulin injection needles: 1. How to choose the needle The needle can directly affect the patient’s feeling when injecting, and it is proved that: the finer the needle, the lower the chance of pain and bleeding. Choose 4-6mm needles to inject more safely. 2, needle reuse is strictly prohibited needle reuse will cause the needle tip deformation, or even partly broken in the body, and it is usually difficult to detect these changes with the naked eye, but also increase the injection pain and injection complications and other adverse consequences. 3, disposal of discarded needles if there is no special back in the box, can be placed in other covered hard-shell containers, such as plastic bottles with lids; under no circumstances should sharp materials be thrown directly into the general (public) garbage bins, in order to avoid needle stab injuries to others.