It is a combination medicine that contains insulin aspart (rapid-acting), and the other is insulin aspart protamine (longer-acting). Insulin aspart has a fast onset of action, and insulin aspart protamine has a prolonged duration of action. Together, they ensure rapid and stable sugar control by enabling the reuptake of sugar in muscle and fat cells and decreasing sugar production in the liver. Try not to stop taking Novomix 50 Flexpen of your own. Let your doctor know about this, as it may cause withdrawal symptoms. Used in Type 1 diabetes mellitus, Type 2 diabetes mellitus.