Insulin therapy absorption

Because of the lipase deficiency, fat-soluble vitamin (A, D, E, and K) deficiencies may occur. Whether lipase activity or bile acids (e.g., in micelle formation) are involved in fat-soluble vitamin absorption with steatorrhea is unclear. Vitamin and zinc deficiencies also may occur as aresult of pancreatic enzyme deficiency. Although pancreatic involvement is predominantly exocrine in nature, insulin deficiency with glucose intolerance also occurs in CF patients, especially as they advance in age. Carbohydrate intolerance is characterized by low insulin concentrations and enhanced peripheral sensitivity to insulin but not by the presence of islet cell or anti-insulin antibodies. Carbohydrate intolerance in CF is not usually associated with the ketosis as commonly occurs in type 1 diabetes. This complication involves an increase in the number of insulin receptors with decreased affinity for insulin. Despite a concomitant increase in tissue affinity for insulin, 8% of CF children over 12 years of age require insulin therapy. 

Occasional patients have antibodies to injected insulin, but the significance of the antibodies is minimal. Human insulin therapy has not totally eliminated insulin allergies, although most patients have a local reaction that will dissipate over time. If the allergic reaction does not improve or is systemic, insulin desensitization can be carried out. Protocols for desensitization are available from major insulin manufacturers. While more common in the animal insulin era, lipohypertrophy is still seen in some patients with longstanding type 1 DM. Such patients give their insulin injections in the same site to minimize discomfort. Because insulin absorption from an area of lipohypertrophy is unpredictable, avoidance of injections into these areas is mandatory. 

Ryysy L, Hakkinen AM, Goto T, et al. Hepatic fat content and insulin action on free fatty acids and glucose metabolism rather than insulin absorption are associated with insulin requirements during insulin therapy in type 2 diabetic patients. Diabetes 2000 49 749-758. 

Koivisto, V. A., 1993, Insulin therapy in type II diabetes, Diabetes Care 16(Suppl. 3) 29-39. Koivisto, V. A., and Felig, P., 1978, Effect of leg exercise on insuhn absorption in diabetic... 

Insulin pump therapy consists of a programmable infusion device that allows for basal infusion of insulin 24 hours daily, as well as bolus administration following meals. As seen in Fig. 40-3, an insulin pump consists of a programmable infusion device with an insulin reservoir. This pump is attached to an infusion set with a small needle that is inserted in subcutaneous tissue in the patient s abdomen, thigh, or arm. Most patients prefer insertion in abdominal tissue because this site provides optimal insulin absorption. Patients should avoid insertion sites along belt lines or in other areas where clothing may cause undue irritation. Infusion sets should be changed every 2 to 3 days to reduce the possibility of infection. 

F. Role in therapy Limited evidence suggests that better control of postprandial glucose may lead to long-term benefits. Both insulin lispro and insulin aspart, because of their rapid absorption after subcutaneous administration, are effective in this regard, but they have not been compared. 

The different mechanisms of action of the various classes of hypoglycemic drugs makes combined therapy feasible the sulfonylureas and meglitinides stimulate insulin production by different mechanisms, the biguanides reduce glucose production by the liver and excretion from the liver, acarbose reduces the absorption of glucose from the gut, and the thiazolidinediones reduce insulin resistance in fat. It is not necessary to wait until the maximal dose of... 

For therapy of local lumps, extravasation, etc., one should first seek to improve the injection technique. Substitution with highly purified insulin is recommended. Injection with purified insulin into the affected area may speed up resorption of the lumps. Lipodystrophy or lipoa-trophy improve after switching to highly purified human or insulin lispro. Lipohypertrophy, on the other hand, often fails to respond to changes in the insulin regimen (161). Varying the injection site may help, but differences in absorption rate then have to be taken into account. 

In conclusion, the pulmonary delivery of insuhn offers an efficient and convenient therapy for diabetic patients. The feasibility of inhaled insuhn is based mainly on the lungs large absorption area of alveoli and their extremely thin walls full of intercellular spaces that make them more permeable than other mucosal sites to large proteins. Generally, inhaled insuhn showed a more rapid absorption than insulin administered by SC injection [59]. One major concern for pulmonary insuhn delivery is the unknown long-term effects of inhaled insuhn within the respiratory tract. Thus, possible long-term problems should be considered when insuhn is administered in this manner [66]. 

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