If you use a syringe to to draw insulin out of a pen some air gets into the pen. It should not have any effect since if you use a vial you inject air into the vial equal to the insulin you want to draw out
If you use a syringe to to draw insulin out of a pen some air gets into the pen. It should not have any effect since if you use a vial you inject air into the vial equal to the insulin you want to draw out