If the insulin injection site is bruised, it may be several things: First, it may be that the force is too strong. Secondly, it may be that the insulin needle was not replaced in time. Because the insulin needle requires disposable use and disposable disposal, but because the cost of the insulin needle is relatively high, some patients can’t throw it away after using it once and use it repeatedly, resulting in the needle becoming a blunt needle, so the damage surface will be larger and bruising of the injection site will easily occur. It is recommended to use insulin needles for injection in a disposable manner as required. Another situation is that the injection site may have damaged a small superficial blood vessel. In these cases, there is no need to be nervous, and the bruised area can be healed naturally by avoiding it when injecting again.