In pre-mixed insulins, rapid- and long-acting insulins are combined into the same product. The pre-mixed insulin in use in Finland is mixed at a ratio of 30/70 (brand name: NovoMix30). The first number indicates the percentage of rapid-acting insulin, the second the percentage of long-acting insulin. For example, 30 units of 30/70 pre-mixed insulin contains 9 units of rapid-acting insulin and 21 units of long-acting insulin.
Pre-mixed insulin is used at mealtimes 1–3 times a day, primarily for the treatment of type 2 diabetes. Pre-mixed insulin can also be used to treat insulin-dependent diabetes, if MDI therapy is not successful or if it is otherwise inappropriate.
Pre-mixed insulin therapy is more formulaic than MDI therapy. The daily routines and amounts of food must remain very similar day after day. Pre-mixed insulins are much less common than in years past.