Insulin pens: features and operation

Insulin pens or pens they are the most widespread method for the administration of insulin in diabetic patients. It is a comfortable and precise mechanism.

What is insulin?

Insulin is a hormone that the pancreas produces and whose function is to regulate the amount of glucose in the blood. This hormone is absent or unusable in diabetes. In fact, diabetes disease can be due to two different causes:

Artificial insulin is the fundamental treatment of type 1 diabetes. To explain how it acts in our body, we can highlight three aspects that characterize it:

  • Start time: It is the time that elapses before insulin reaches the blood and begins to lower the glucose level.
  • Peak peak action: this is called the point at which insulin has its maximum power with respect to the reduction of blood glucose.
  • Duration of effect: It is the time that insulin continues to reduce the glucose level.

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Types of insulin

Insulin types are classified according to the duration of their effect and the time it takes to do so. According to this, we have:

  • Quick action: takes effect after 15 minutes after injecting. It reaches its maximum action at the time and is effective for two or four hours.
  • Brief-acting insulin: This type of insulin reaches the bloodstream 30 minutes after the injection. Its maximum effect is achieved at two or three hours and is effective for three and six hours.
  • Intermediate action: reaches blood flow between two and four hours after injection. It has its maximum effect of four to twelve hours after injection. The intermediate-acting insulin is effective for approximately twelve to eighteen hours.
  • Long-acting insulin: It usually reaches the blood several hours after the injection and keeps the glucose level low for 24 hours.

Types of insulin pens

There are two types of insulin pens:

  • Disposable pens: they are used only once and when the insulin in the cartridge is finished, it is discarded.
  • Reusable pens or pens: They have a device that allows you to change the cartridge when the insulin runs out.

The amount of insulin injected can be regulated by a dial to adjust the dose depending on the need you have. For safety, the needles should be changed every time you inject yourself.

Advantages and disadvantages of insulin pens

As for the advantages of insulin pens, your injection is faster and easier because the dose is already prepared. In addition, by its dosing system, you can inject insulin more accurately. It also has the advantage of its format, which facilitates transport and use.

However, insulin pens also have disadvantages such as not being able to mix different types of insulin. They also have the disadvantage that they need to be purged and tested before each puncture. In this way, you waste insulin before each injection.

How does an insulin pen work?

Insulin pens, both disposable and rechargeable, carry a needle with which you inject. These needles, in the case of rechargeable pens, must be changed after each use.

Steps to follow

Before performing the injection, you should wash your hands and adjust the dial with the necessary insulin units. Then, keep the pen pointing with the needle up and press until you see a drop. This drop will be proof that it works correctly.

Clean the skin where you are going to do the puncture and regulate the dial until you reach the necessary dose. Then, squeeze the skin where you are going to inject and push the needle with a direct and fast movement. Then, squeeze the pen with your big toe to get the dose and discard the needle.

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How to preserve insulin pens

For proper preservation of insulin pens, temperature and time must be taken into account. It is advisable to store it in the fridge at a temperature between 4 and 8 degrees. In addition, insulin should not be exposed to intense light and heat sources.

It is not convenient that it goes below 2 degrees, since, if it did, it would lose its effectiveness. However, even if it is kept in the fridge, It will be in good condition for the period of time indicated on the expiration date of the container.


Insulin pens are the most accurate, fastest and easiest method of administering insulin in diabetic patients. Remember that Insulin pens can be used within 30 days after first use.