What is insulin injection?
Insulin injection is a form of treatment in which insulin is injected into the body to help control blood sugar levels in diabetes patients.
How it works
Insulin is a hormone produced by pancreatic cells. It is what allows blood glucose (sugar) to enter the cells and to keep blood glucose levels within normal limits.
If you have diabetes, your glucose levels will continue to rise after you eat because there is not enough insulin to move the glucose into your body cells.
Insulin administration helps prevent diabetes complications by keeping your blood sugar within a desired range.
Left untreated, high blood glucose levels can eventually lead to complications such as blindness, nerve damage, kidney damage, heart attacks or strokes.
Types of insulin
There are several types of insulin. They differ in:
- How quickly they start to lower your blood glucose
- Time taken to reach their highest activity
- How long they continue to work
Type of insulin preparation |
How it works |
Rapid-acting |
* Ideal for preventing blood sugar spikes after you eat * Works much faster, within 15 minutes |
Long-acting |
* Helps the body use glucose released by your liver and keeps glucose levels from rising too high so the body continually has energy * Takes a longer time to take effect, between 1 – 3 hours * Works for a longer period of time, 18 hours or beyond |
Why do you need insulin injection?
In type 1 diabetes, the body makes little or no insulin, due to the destruction of the pancreatic cells responsible for insulin secretion. Type 1 diabetes patients need multiple daily injections of insulin into the body to survive.
In type 2 diabetes, the body has resistance to insulin and requires more insulin than usual, and the pancreas is not able to produce enough insulin to combat this resistance. Type 2 diabetes patients may also need insulin, especially if the duration of diabetes is long.
What are the risks and complications of insulin injection?
Insulin should be prescribed by a doctor and dose adjustments should be supervised.
Taking insulin may also result in some side effects, such as:
- Low blood sugar
- Initial weight gain
- Lumpy or scarred tissue from too many injections on the same part of the body
- Rashes on the injection site or, in rare cases, all over the body
As the exact dose of insulin needed is different for everyone, your doctor will need to calculate the dose you require.
Too much insulin
In the event of an insulin overdose, blood sugar concentrations can become too low. This can lead to a coma and even death.
To raise blood glucose levels, orange juice, table sugar or any other pure form of sugar is usually given. If the patient is in a coma, glucose is injected into the blood stream.
Insufficient insulin
If the insulin dose is insufficient, the diabetes will not be controlled and in poorly controlled cases, this can lead also to severe consequences, such as a coma.
A test of the blood glucose levels is needed to tell the difference between the 2 types of comas. A low blood glucose level means the patient has received an overdose of insulin. If the levels are high, it means they have not received enough insulin. Either case should be treated as an emergency in the hospital.
What can you expect during insulin injection?
Insulin cannot be taken orally because it is digested and destroyed by the stomach. The only way to receive insulin currently is by injection.
How to inject insulin
There are different ways to inject insulin, such as syringes, insulin pens, insulin pumps and jet injectors. Your doctor will help you decide which technique is best for you.
Syringes or pen forms of insulin are the most common and inexpensive method of insulin delivery.
Where to inject insulin
For easier, safer and more comfortable injections, it is important to know where to inject your insulin. Insulin is injected into the fatty area under the skin. Your doctor or nurse will advise you on which area to inject.
There are 3 main injection areas:
- Abdomen (fastest absorption)
- Arm
- Thigh and buttocks (slowest absorption)
Tips for insulin injection:
- Avoid changing injection areas frequently. This may cause your blood sugar levels to fluctuate, as insulin is absorbed into the blood at different rates from different areas.
- Do not inject your insulin into the same exact spot each time. This may cause thickened scar tissue to form which can affect insulin absorption.
When to have your insulin injections
This depends on the formulation of insulin. In Singapore, the most common meal-time insulin is rapid acting insulin with a fast onset of action. This is injected 15 minutes before your meals. This is because the insulin will move into your blood to match the rise in blood sugar levels from the meals.
Note: If you are using short-acting insulins, you will have to wait 30 minutes before eating your meal. The insulin is absorbed more slowly than a rapid-acting insulin.