Therapeutic Effects and Rationale for Use

Exogenous insulin is administered to replace normal pancreatic hormone production in type 1 diabetes (IDDM). Exogenous insulin is crucial in maintaining normal glucose levels and proper metabolic function because beta cell function is essentially absent in patients with type 1 diabetes. Without exogenous insulin, the general health of type 1 patients is severely compromised, and they often succumb to the metabolic and neurovascular derangements associated with this disease. 

Insulin may also be administered in some cases of type 2 diabetes to complement other drugs (oral antidiabetic agents) and to supplement endogenous insulin release.64,70 In type 2 diabetes (NIDDM), exogenous insulin basically makes up the difference between the patient s endogenous hormone production and his or her specific insulin requirement. In addition, many patients with advanced cases of type 2 diabetes ultimately require supplemental insulin because other interventions (diet, exercise, other drugs) are not able to adequately control this disease.35 

On the other hand, it is sometimes advantageous to administer forms of insulin that are absorbed more slowly and have a more prolonged effect than regular human insulin (see Table 32-2). These intermediate- 

Type of Insulin Rapid-acting Onset Effects (hr) Peak Duration Common Trade Name(s) Human Animal  

Regular insulin 0.5-1 2-4 5-7 Humulin R Novolin R Regular lletin II 

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