Insulin preparations, pharmacokinetic

Table 11.4 Some pharmacokinetic characteristics of short, intermediate and long-acting insulin preparations...

Knowledge of the patient s quantitative and qualitative meal patterns, activity levels, pharmacokinetics of insulin preparations, and pharmacology of oral antihyperglycemic... 

Additionally, insulins may be characterized as analogs, defined as insulins that have had amino acids within the insulin molecule modified to impart particular physiochemical and pharmacokinetic advantages. Table 72-8 summarizes available insulin preparations. 

Knowledge of the patient s quantitative and qualitative meal patterns, activity levels, pharmacokinetics of insulin preparations, and pharmacology of oral antidiabetic agents for type 2 DM are essential to individualize the treatment plan and optimize blood glucose control while minimizing risks for hypoglycemia and other adverse effects of pharmacologic therapies. 

Insulin, whatever its source, may be formulated in a number of ways, generally in order to alter its pharmacokinetic profile. Fast (short)-acting insulins are those preparations that yield an elevated blood insulin concentration relatively quickly after their administration (which is usually by s.c. or, less commonly, by i.m. injection). Slow-acting insulins, on the other hand, enter the circulation... 

Since the concentrations of insulin to be administered in the sheep model would have been large, the insulin-loaded chitosan nanoparticles were not investigated in that model. However, the pharmacodynamics and pharmacokinetics of various insulin-chitosan preparations were compared with postloaded insulin-chitosan nanoparticles. It was found that chitosan solution and chitosan powder formulations were far better, with the chitosan powder formulation showing a bioavailability of 17% as against 1.3 and 3.6% for the chitosan nanoparticles and chitosan solution [72], The effects of the concentration and osmolarity of chitosan and the presence of absorption enhancers in the chitosan solution on the permeation of insulin across the rabbit nasal mucosa in vitro and in vivo were investigated, and the same... 

Insulin is used for the treatment of Type-I and for Type-II diabetes mellitus, when other therapeutic measures, i.e. appropriate diet and oral antidiabetics, are not sufficient to produce normoglycaemia. The physiological actions of insulin including recent advances in our knowledge on signal transduction have been discussed above (chapter 4). Since treatment of diabetes with insulin attempts only to supplement inadequate insulin secretion, this chapter will concentrate on pharmacokinetics, unwanted effects and clinical applications of insulin and its pharmaceutical preparations. 

NPH and Lente insulins differ in their ability to form mixtures with neutral insulin solutions (Berger et a/., 1982 Heine eJ a/., 1984 Forlani et al, 1986 Brange et al., 1987). Both can be mixed with regular insulin immediately before injection. Mixtures of NPH with regular insulin preserve their pharmacokinetic characteristics over time. This is not the case with Lente/regular mixtures because the surplus of zinc ions in the Lente part will combine with part of the insulin in solution and change it into a Semilente-like preparation. 

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