1, the harm of repeated use
First of all, there will be residual insulin crystals in the barrel of the used needle, repeated use will clog the needle, affecting the accuracy of the next injection of insulin dosage, and unstable blood sugar control.
Secondly, after the first use, bacteria in the air and on the tip of the needle can enter the cartridge through the needle when it is used again, contaminating the medication and affecting its efficacy, as well as increasing the risk of localized infection.
In addition, in order to reduce the patient's pain when injecting, insulin pen needles are designed to be very thin, and it is easy to break the needles in the body when reused, and the broken needles will travel in the body, which is not easy to take out. And repeated use tends to make the tip of the needle burrs, bends and barbs, leading to bleeding and abrasions at the injection site, which can also exacerbate the pain. In the long run, repeated use of deformed needles can cause micro-trauma to the subcutaneous tissue, which gradually accumulates to form subcutaneous fat nodules. The hard knots will affect the efficiency and speed of insulin absorption, reducing the effectiveness of drug delivery and making it more difficult to control blood sugar.
So, it is not recommended that diabetic patients reuse pen needles for injections, so as not to affect the efficacy of the drug and damage the skin and subcutaneous tissue.
2. Notes on injecting insulin
1. To ensure that insulin is injected under the skin, the skin must be pinched and injected at a 45-degree angle if a longer pen needle or insulin syringe is used for injection. Most adults injecting with an insulin pen do not need to pinch the skin and inject directly. In addition, after pushing the plunger fully to the bottom, the needle should remain in the skin for 10 seconds, removing it before releasing the skin fold.
2. Suitable areas for insulin injections include the abdomen, outer thighs, outer 1/4 of the arms, and buttocks, which are favorable for insulin absorption and have less nerve distribution. Due to the difference in the onset of action of different insulins, the injection site should be selected. For example: short-acting insulin is preferred to be injected into the abdomen; intermediate-acting insulin is preferred to be injected into the thighs and buttocks; premixed insulin and its analogs are preferred to be injected into the abdomen before breakfast, and in the evening they are preferred to be injected into the thighs or buttocks in order to avoid the occurrence of hypoglycemia in the night.
3. Injecting during meals. Injecting insulin at mealtime is very common, and it is mainly rapid-acting insulin. Fast-acting insulin is characterized by: opening up the hexameric form of conventional insulin and becoming a monomer structure, which does not need to be separated into monomers after injection, fast absorption and short onset of action. Meals do not need to be injected in advance, while the injection must be immediately after eating, otherwise hypoglycemia may occur.
4. Since insulin is a growth factor, repeated injections at the same site will lead to subcutaneous hardening, lowering the rate of insulin absorption at that site, which in turn makes the blood sugar unstable. Therefore, the usual injection must pay attention to the rotation of the injection site. The rotation of injection sites includes "big rotation" between different injection sites and "small rotation" within the same injection site. The "big rotation" refers to the rotation of injections in the abdomen, arms, thighs and buttocks, and there are two methods, one is according to the left side of the week, the right side of the week; the other is according to the left side of the week, the right side of the week; and the "small rotation" requires that the injection point is about 1 finger's width away from the last injection site, and the injection point is about 1 finger's width away from the last injection site. The "small rotation" requires a distance of about 1 finger width from the last injection point, and try to avoid reusing the same injection point within a month.
5, patients in the process of insulin injection should comply with the principle of "one needle, one change". Otherwise, repeated use will cause the tip of the needle to blunt, which may lead to subcutaneous fat hyperplasia, and even the accident of leaving the needle in the body.
6, injection after meals. Some patients' conditions are more suitable for injection after meals. For example, patients with type 1 diabetes, when the preprandial blood glucose is low, at 2.8~3.9mmol/L, can be changed to postprandial injection of insulin, at the same time appropriate to eat more; the use of rapid-acting insulin, can also be injected after meals.
7, used up needles can not be discarded, must be put into the hard shell container with a lid to avoid contamination.
3, insulin injection side effects
1, causing hypoglycemic reaction
The hypoglycemic reaction to insulin is the most common and important side effect in the use of insulin therapy. When the insulin dose is already close to the required dose, the change of 1 unit of insulin dose may cause hypoglycemia, which should be paid enough attention, and should be treated and dealt with in time once it is found.
2, causing allergic reactions
An allergic reaction to insulin injection is mainly due to immunopathological changes, because insulin is an animal product or product does not exist. Gene artificial combination of human insulin does not have such reactions. Insulin national cotton reaction epitope injection local and around the appearance of urticaria, erythema and skin itching; peripheral allergic reaction can appear generalized urticaria, angioneurotic edema, anaphylactic purpura and so on. Most of them can subside naturally, and anaphylactic shock can occur in rare cases.
3, leading to blurred vision
In the process of insulin therapy, sometimes patients will feel blurred vision, is due to the rapid decline in blood glucose during treatment, affecting the lens and vitreous osmotic pressure, so that the water in the vigilance of the overflow of refractive error, resulting in hyperopia. However, this change is temporary and can disappear quickly as blood glucose concentration returns to normal.
4, insulin edema
High-dose insulin injections can occasionally be taken together with peripheral tissue edema, especially when the metabolism is poorly controlled in patients rapidly corrected. Insulin edema is most often seen on the face, but can also occur with the extremities, and in severe cases, ascites can occur. It usually resolves on its own, and medication is needed if necessary.
5, fat atrophy and subcutaneous nodules
Injection of local skin redness, swelling, fever and subcutaneous nodules occur, mainly due to the injection of insulin protein and other impurities. In addition, frequent injection of the same site can appear subcutaneous fat hygiene or hyperplasia, so it is necessary to frequently change the injection site.