Insulin formulations long/intermediate acting

Insulin preparations that are commercially available differ in their relative onset of action, maximal activity, and duration of action. Conjugation of the insulin molecule with either zinc or protamine, or both, will convert the normally rapidly absorbed parenterally administered insulin to a preparation with a more prolonged duration of action. The various formulations of insulin are usually classified as short acting (0.5 to 14 h), intermediate acting (1 to 28 h), and long acting (4 to 36 h). The duration of action can vary, however, depending on injection volume, injection site, and blood flow at the site of administration. 

The treatment of type 1 diabetes is the subcutaneous injection of insulin, as insulin cannot be administered orally because it would be broken down in the stomach due to the low pH. Initially, animal insulin was used in the treatment of diabetes, since bovine and porcine insulin are structurally similar to human insulin. Nowadays, most of the insulin used in the treatment of diabetes is human insulin produced via recombinant DNA (see Ch. 27). There are a number of insulin formulations available, e.g. short-, intermediate- or long-acting and biphasic (a mixture short- and intermediate-acting insulin), and these are described in more detail in Chapter 27. There is a range of therapy protocols indicated, based on the individual condition of the patient. 

Actrapid/Velosulin/ Monotard/ Insulatard/ Protaphane/ Mixtard/ Actraphane/ All contain recombinant human insulin produced in S. cerevisiae formulated as short/ intermediate/long acting product) Identical to native human insulin Novo Nordisk 2002 (EU)... 

Regular insulin typically is given subcutaneously, often in combination with an intermediate-or long-acting preparation. Special buffered formulations of regular insulin are available for use in subcutaneous infusion pumps that are less likely to crystallize in the tubing during the slow infusion associated with this type of therapy. 

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