Lipodystrophy, insulin injection site

Insulin, administered subcutaneously, may cause either lipoatrophy or lipohypertrophy. Lipoatrophy is the breakdown of adipose tissue at the insulin injection site causing a depression in the skin at the injection site and occasionally at distant sites also. It may be the result of an immune response or the use of less than pure insulin. Some findings suggest that total lipodystrophy syndrome results from the inflammatory destructive process of adipose tissue (Yanagawa et al., 1990). Injection of human or purified porcine insulin into the site over a 2-4-week period may result in subcutaneous fat accumulation. 

Unwanted effects. Hypoglycemia results from absolute or relative overdosage (see p. 260). Allergic reactions are rare—locally redness at injection site, atrophy of adipose tissue (lipodystrophy) systemically urticaria, skin rash, anaphylaxis. Insulin resistance can result from binding to inactivating antibodies. A possible local lipohypertrophy can be avoided by alternating injection sites. 

Highly purified (single component) and human Insulins Local insulin allergy, immunologic insulin resistance, injection-site lipodystrophy temporary insulin use (ie, surgery, acute stress type 2 diabetes, gestational diabetes) newly diagnosed diabetic patients. 

Somogyi effect, including rebound hyperglycemia with chronically excessive insulin dosages systemicallergic reaction, marked by rash, angioedema, and anaphylaxis lipodystrophy or depression at injection site due to breakdown of adipose tissue lipo-hypertrophy or accumulation of subcutaneous tissue at injection site due to inadequate site rotation Rare... 

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. 

Other adverse reactions to insulin are lipodystrophy (atrophy or hypertrophy) at the injection sites (rare with purified pork and human insulin), after they have been used repeatedly. These are unsightly, but otherwise harmless. The site should not be used further, for absorption can be erratic, but the patient may be tempted to continue if local anaesthesia has developed, as it sometimes does. Lipoatrophy is probably allergic and lipohypertrophy is due to a local metabolic action of insulin. Local allergy also is marrifested as itching or painful red lumps. 

Infrequent Somogyi effect (rebound hyperglycemia) with chronically excessive insulin doses. Systemic allergic reaction (rash, angioedema, anaphylaxis), lipodystrophy (depression at injection site due to breakdown of adipose tissue), lipohypertrophy (accumulation of SC tissue at injection... 

The two forms of lipodystrophy, though less common today in people with diabetes, still occur. Lipohypertrophy is caused by many injections into the same injection site. Due to insulin s anabolic actions, a raised fat mass is present at the injection site with resultant variable insulin absorption. Lipoatrophy, in contrast, is thought to be due to insulin antibodies, with destruction of fat at the site of injection. Injection away from the site with more purified insuhn is recommended, though several reports of lipoatrophy with lispro have been reported. 

Skin Lipodystrophy at the site of insulin injection is well documented, although the mechanism remains unknown, and cases continue to be reported [8 ]. However, other effects can occur at the site of injection. 

The effects of insulin are modified by various factors. The speed and extent of absorption of insulin depends, for example, on the site of injection (1), the depth of the subcutaneous injection, skin temperature (2), the presence of lipodystrophy, and variation in the extent of inactivation of injected insulin. The disposal of insulin depends on many factors. Exercise and hard work lower the blood glucose and thereby increase the effect of insulin. Infections and obesity reduce its effect. The timing of food intake and the composition of meals are also related to the action of insulin. A thin layer of fat, as sometimes occurs in the upper arm or in the thighs of thin men, can result in intramuscular injection, leading to faster absorption of long-acting insulins. This can reduce the absorption time by half (3). The major factors that affect the fate of injected insulin (and thereby also its risks) are listed in Table 1 (4). 

Lipodystrophy, lipoatrophy, or lipohypcrtrophy can be a consequence of chronic local insulin reactions that can be elicited by less pure as well as by highly purified preparations (140), but such reactions can also develop at sites distant to the injection. 

Adverse effects observed with insulin Note lipodystrophy is a local atrophy or hypertrophy of subcutaneous fatty tissue at the site of injections. 

Patients should standardise their technique to ensure injection is s.c. Inadvertent i.m. injection of an overnight dose of an extended duration insulin can lead to inadequate early morning control of blood glucose. Sites of injection should be rotated to minimise the now rare local complications (lipodystrophy). Absorption is faster from arm and abdomen than it is from the thigh and buttock. 

The effects of insulin are modified by various factors. The speed and extent of absorption of insulin depends, for example, on the site of injection (1), the depth of the subcutaneous injection, skin temperature (2), the presence of lipodystrophy, and variation in the extent of inactivation of injected insulin. The disposal of insulin depends on many factors. Exercise and hard work lower the blood glucose and thereby increase the effect of... 

The most common and important form of insulin-induced immunologic complication is the formation of insulin antibodies, which results in resistance to the action of the drug or allergic reactions. Human insulins ate less antigenic than insulin from animal sources. Lipodystrophy, a change in fatty tissue at the site of injection, was relatively common in the past. Use of more purified, less antigenic forms of insulin has almost eliminated this complication. 

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