People with diabetes, especially type 1, are required to adequately control their blood sugar levels, so they must manage their insulin needs by injection up to several times a day. However, the constant need to maintain this injection regimen can be both stressful and disruptive.

As a result, insulin pens are growing in popularity as an alternative to the traditional syringe and vial for injections since they are more convenient and easier to use.  Insulin pens may be disposable or reusable, and include an insulin dose cartridge, a dosage indicator and a disposable needle.  Once it is time for an insulin injection, the needle is attached to the tip, and insulin is injected subcutaneously into fatty tissue.

It is important to use an insulin pen correctly to ensure that all required insulin has been injected for optimal use and consistent blood sugar levels. Choosing the right injection site and properly handling the pen will ensure its safe and effective use.

Female injecting insulin pen

Choosing the Right Insulin Pen

There are two main types of insulin pens available: disposable and reusable. Within each type, they vary in price, the type of insulin held, and dosing levels.

Disposable pens contain a prefilled insulin cartridge that is disposed of once the cartridge is empty, or the pen has been in use for 28 or 32 days (depending on the insulin type).

Reusable pens contain replaceable insulin cartridges that can be placed into the pen and then removed when all the insulin has been injected, leaving the pen ready for the next cartridge.  The disposable needle must be replaced after each insulin injection. If cared for properly, these insulin pens can last for several years.

While reusable pens are initially more expensive than disposable pens, the replacement cartridges for these pens are less expensive than the replacement disposable pens, so both pens are actually similarly priced over the long term.

Another consideration when choosing a pen is how the insulin dosages are handled. Some pens can provide doses in half-unit increments (for example, 1.5 units), while others dose in whole units. Lower-dosing pens are often better for children who have type 1 diabetes and require smaller doses of insulin.

Additional factors to consider when choosing an insulin pen include the number of units of insulin the pen can hold when full, how large a total dose can be injected; how the amount of insulin remaining is indicated on the pen, and whether your insurance covers a specific insulin pen that is on their list of preferred prescription drugs.

Insulin Pen

Choosing the Right Pen Needles

The pen needles are easily screwed onto the top of the pen, but you must change the needle after each injection in order to lower the chance of infection. Most pen needles sold will fit any of the insulin pens. These needles come in various lengths, usually between 4 and 12 mm, and various thicknesses (gauges).


A shorter needle is very effective for all body types. The goal is to deliver the insulin just below the skin without hitting the muscle beneath, as this affects the rate of insulin absorption.


A higher gauge needle is a thinner needle and causes less pain. However, if a large dose of insulin is needed at one time, a thicker needle may make for faster insulin delivery and help to avoid medication leaking out of the skin.

Storing your pens

An important first step is to check the expiration dates of the insulin pen cartridges, keeping in mind that expiration dates vary with the type of insulin used.  New insulin pens should always be stored in the refrigerator, but once a pen has been used, it must be kept at room temperature (15 C – 30C) and out of direct sunlight.

According to the American Diabetes Association, when a person stores insulin at room temperature, it is good for 28 days to 32 days depending on the type of insulin.

Insulin pens should never be stored with the needle attached, even if the attached needle is new. This can affect the sterility and cleanliness of the needle, interfere with the insulin dose given, and increase the risk of infection.

Insulin storage

The Benefits of Using Insulin Pens

Insulin injections are more convenient with pens because they combine the medication and syringe in one handy unit. Unlike traditional syringes, these pens come preloaded with insulin, including premixed types.  They are also easy to use: just twist or snap on a new needle, dial the dose needed, inject the insulin, and dispose of the used needle into a needle-safe, sharps container.

Since certain insulin pens are disposable, so you can get rid of the pen once the insulin is used up or expired, while reusable pens continue their use once a new insulin cartridge is inserted.

One result of this ease of operation is greater confidence in the accuracy of the insulin doses administered by these pens.  The desired doses can be pre-set on the pen’s dosage dial.

This is especially useful for diabetics who have impaired vision or manual dexterity issues.

A study conducted by the American Diabetes Association showed that 73% of people using insulin pens were confident about their greater dose accuracy, while only 19 percent were as confident that they were getting the right dose using vials and syringes.

Since these pens are portable and travel-friendly, they are also great time savers, and really helpful for young diabetics who need to inject insulin at school. The small and thin needle sizes on insulin pens also reduce fear and pain, an important consideration when working with younger diabetic children.

It is especially helpful that many brands of insulin pens are now color-coded and use different designs to help identify which type of insulin they contain, ensuring that the right insulin will be administered. A new developmen