Insulin: the blood sugar lowering hero and sugar-friendly partner!

Author: Nie Xuanxuan, The Fifth Medical Center, PLA General Hospital

Reviewer: Jin Bo, Chief Physician, Fifth Medical Center, PLA General Hospital

At present, the prevalence of diabetes is severe, and the number of patients worldwide continues to rise, which has become one of the major issues affecting public health. In the face of this challenge, the importance of insulin as an important drug for the treatment of diabetes is self-evident. Insulin is a hormone secreted by beta cells in the pancreas and is essential for regulating blood sugar balance in the body. For patients with type 1 diabetes and some patients with type 2 diabetes, when oral hypoglycemic drugs cannot meet the needs of blood sugar control, insulin treatment becomes an indispensable means.

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1. How many types of insulin are there in clinical use? What are the requirements for injection time?

The classification of insulin preparations commonly used in clinical practice, commonly used drugs and injection times are shown in the figure below.

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2. What should we pay attention to when storing insulin?

Insulin is very "delicate" and needs to be stored with care. The stability of insulin is easily affected by temperature, light and vibration. When the temperature is below 0°C or above 25°C, the activity of insulin will be destroyed or reduced. Therefore, the following matters should be followed when storing insulin.

1. Unopened insulin: should be stored in an environment of 2-8°C, avoid freezing and direct sunlight.

2. Opened insulin: should be stored away from light at room temperature (valid for 28 days after opening and cannot exceed the shelf life). Insulin is more stable at room temperature and the pain during injection is less. If the room temperature exceeds 25°C, please store the opened insulin in the refrigerator at 2-8°C. Take it out of the refrigerator 30 minutes in advance before use. Rewarm the insulin at room temperature before use. Repeated temperature changes will affect the effectiveness of insulin.

3. The storage location of insulin in the refrigerator: The placement of insulin should be fixed, and it should not be placed on the refrigerator door, because repeated opening and closing of the refrigerator door will cause the insulin to oscillate and affect the stability of the drug.

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3. What should you pay attention to when injecting insulin daily?

1. It is not advisable to inject insulin when fasting due to examination or medical condition to avoid hypoglycemia.

2. Do not change the insulin injection dose at will to avoid affecting blood sugar fluctuations or causing hypoglycemia.

3. Disinfect the skin with ethanol before injection.

4. Change the injection site: The suitable sites for insulin injection are the abdomen (beyond 2.5 cm around the navel), the outer thigh, the outer upper arm and the buttocks (usually the outer upper part) subcutaneously. Insulin is absorbed fastest in the abdomen, and slower in the upper arm, thigh and buttocks. Once fat hyperplasia, pain, nodules, inflammation or infection occurs at the injection site, injection should be stopped immediately and the injection site should be changed. If injection is made in the same area, it should be at least 1 cm away from the last injection site; avoid reusing the same injection site within 1 month.

5. Mix the insulin before injection: Short-acting and rapid-acting insulin are colorless and transparent in appearance and can be injected directly; some premixed insulins are opaque in appearance and are composed of more than one component. Therefore, before use, the insulin should be rolled horizontally and turned upside down 10 times each to fully mix the liquid in the bottle until the insulin becomes a uniform white cloudy liquid.

6. Skin pinching and needle insertion angle: Whether the skin needs to be pinched depends on the thickness of the skin at the injection site and the length of the needle used. When using a shorter needle (4 mm or 5 mm), there is no need to pinch the skin and the needle can be inserted vertically. When using a longer needle (≥6 mm), it is necessary to pinch the skin and/or insert the needle at 45° to reduce the risk of intramuscular injection, and then loosen the skin after pulling out the needle.

7. Needle retention time: When using an insulin pen for injection, you should wait for at least 10 seconds after fully pressing the thumb button before pulling out the needle to ensure that all the medicine is injected into the body and to prevent leakage of the medicine.

8. Needle replacement time: Use disposable needles and replace them with new disposable needles before each injection.

The correct process for insulin injection is shown in the figure below.

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