Written By: ADCES staff and reviewed by ADCES clinical staff
Updated: June 8, 2023
Welcome to our Insulin Pen Overview and Frequently Asked Questions (FAQs) page. As healthcare providers, we know that insulin pens are widely used for insulin delivery and while they are relatively simple to use, many have questions about their usage and best practices. In this section, we address some common queries related to insulin pens, including their functioning, selection, storage, disposal, and more.
Pens come as either disposable prefilled pens or reusable pens loaded with a cartridge that you can fill with insulin from a vial. Many of the reusable pens are considered “Smart Pens” because they are connected to an app that provides data such as a dose and time stamp log and reminder options, or connectivity to a glucometer or continuous glucose monitor (CGM).
The disposable pens are prefilled with insulin and available from a pharmacy in the pre-filled state. The reusable pens are either filled by the user with pre-filled cartridges of insulin or by adding insulin from a vial to a compatible cartridge.
As previously mentioned, connected insulin pens have additional features for management. These include the ability to log dose, food, events and activity, and glucose values. They allow for data interpretation, the ability to set reminders, connect to glucometers and continuous glucose monitors, and use of the data for dosing recommendations.
The decision on which insulin pen to prescribe is influenced by the providers recommendation for insulin type, insurance coverage (formulary), and whether a connected pen (Smart Pen) or conventional pen is the best option for them.
To see all pens and insulin delivery devices available in the US, view our find and compare insulin delivery devices page.
Fore detailed instructions, read Learning How to Inject which includes choosing a device, injection techniques, and site rotation charts.
Additional tips include:
Insulin pens are available as both reusable and disposable. Disposable pens require a prescription for the insulin as a pen option not a vial. Reusable pens require a prescription for the reusable pen and also require a prescription for the prefilled insulin cartridge (the user needs one prescription for the reusable pen and one for the insulin and refills). The cartridges or disposable pens are disposed of when they are empty or after 28-32 days (after opening depending on the insulin).
Store unused insulin pens, insulin filled cartridges, or insulin in a vial in the refrigerator in the refrigerator door. This makes it easier to find and prevents it from being pushed to the back of the refrigerator where it may be at risk of freezing. Insulin will have an expiration date on it, encourage the person with diabetes to check this date before they leave the pharmacy or upon receiving it by mail. An awareness of expiration dates and using their insulin supplies in order of their expiration will help individuals avoid wasting insulin because it expired. Things do happen and sometimes insulin does expire- talking about that upfront will prevent the person with diabetes from blaming themselves unnecessarily. If this happens often, a log book may be helpful for supply management.
Insulin pens can be kept at room temperature for varying amounts of time. Make sure that the user is aware how long insulin can be kept out at room temperature for their prescribed insulin.
Most disposable insulin pens and insulin cartridges need to be discarded 28-32 days after opening. This is dependent on the insulin and it is recommended that you go over this information during their insulin pen education.
Insulin pens and the insulin that they hold are covered by insurance. There is a co-pay cap of $35.00/insulin for individuals with private insurance and individuals on Medicare who get insulin through their prescription benefit (Capping the cost of insulin at $35.00 under Medicare Part B coverage will take effect July 1, 2023).
You can and will need to travel with your insulin pens, additional insulin, and supplies. It is advised to pack insulin in your carry-on bag instead of your checked luggage to avoid damage from changes in air pressure or temperature extremes in the luggage compartment of an airplane. When the person with diabetes is traveling by plane, provide them with a copy of their prescription for all medication as well as any extra supplies that they will be carrying with them that requires a prescription. This helps them get through airport security easier (hopefully) and facilitates getting supplies if they need them while they are traveling.
According to the FDA insulin may be left unrefrigerated at a temperature between 59°F and 86°F for up to 28 days. Cooling packs designed for keeping medications cold but not frozen, or a refrigerated cooling device may be helpful if temperatures are going to be questionable. Remind the user to not use insulin that has been frozen, to keep insulin out of direct heat or light and to avoid exposing insulin to extreme temperatures.
A TSA Disability Card is helpful to facilitate an easier travel experience.
Medication that is over 3.4 fluid ounces is exempt from the TSA prohibitions as is juice, gel, glucagon, etc. to treat hypoglycemia.
You are allowed to request that TSA hand checks your diabetes supplies and does not send it through the X-ray machine. While Insulin can withstand the X-ray machine, you are permitted to request hand checking of your medication and supplies.
The recommendation is to use a new needle for each injection or to change it at least 1x/day. Dispose of used needles in a sharps container. Repurposing a clean empty laundry detergent bottle for disposal works for some people based on the local sharps disposal ordinances. See guidelines for your locale here.
NEVER throw sharps “loosely” into regular garbage- an injury may occur when disposing of items that are not handled properly.
It is a good idea to check injection technique, discuss site rotation, and periodically observe the person giving an injection if possible. Assure the person with diabetes that all questions about giving themselves an injection are valid and anything that they notice out of the ordinary should be brought to your attention. Since there are no nerve endings in the layer of fat below the skin, the injection should not be very painful. Advise the person with diabetes, that if the injection is causing pain, that they should let you know about it.
Common side effects of using an insulin pen include:
Lipohypertrophy: Lipohypertrophy is a collection of fatty tissue that forms under the skin that occurs due to repeated injections in the same place. It is commonplace in people with diabetes, can impact your body's ability to absorb insulin and has the potential to cause serious complications. One way to decrease the likelihood of lipohypertrophy is to practice site rotation that uses different parts of the body and rotates within the same sight in a large area. This resource provides guidance and charts for educating on and logging site rotation locations.
Hypoglycemia: A person who uses insulin to manage their diabetes is at risk of hypoglycemia. Understanding the symptoms of hypoglycemia and how to treat a hypoglycemic event are an integral part of education around using insulin. Everyone who has a prescription for insulin should also have a prescription for glucagon and be educated in how to use it and how to educate those around them in case of an emergency where they themselves cannot act.
Redness, swelling, or itching at the injection site may also occur as a result of injecting insulin. Guide those with diabetes to report any of these side effects to you as soon as they are able.
Insulin pens are clearly labeled with the medication name and reusable pens are color coded. Recommending that a person with diabetes who uses more than one insulin adds further labeling with a permanent market or home-made label may help to ensure that no mix-ups occur. In addition, encouraging them to check the label every time they inject and not function on auto-pilot will further help avoid mix-ups.
Most pens hold 3 ML (300 units of insulin for U100, 600 units of insulin for U200, 900 units of insulin for U300, etc.).
Insulin may be left unrefrigerated at a temperature between 59°F and 86°F for up to 28 days.
Keep insulin out of direct heat or light and avoid exposing it to extreme temperatures (hot or cold) to help ensure effectiveness.
Most pens can be used with various needles. It is important to help the person with diabetes choose the most appropriate needle size for them based on needle length and diameter in order to only inject into the fat pad sitting directly underneath the skin. Listen to this The huddle podcast for more information.
As this may change, you can search for this on danatech by selecting “Half Unit Dose Capability” on the Medicine Delivery page.
Sometimes a drop of blood will leak out after the injection, have the user press the area lightly with clean gauze or a tissue. As long as they held the pen in for the entire dose and counted to 10 after the dose was administered, they will have gotten the entire dose. If they see a fluid leaking out and it smells like insulin, have them contact the office, so you can have them monitor their glucose levels for safety.
This site and its services do not constitute the practice of medical advice, diagnosis or treatment. Always talk to your diabetes care and education specialist or health care provider for diagnosis and treatment, including your specific medical needs. If you have or suspect that you have a medical problem or condition, please contact a qualified health care professional immediately. To find a diabetes care and education specialist near you, visit the ADCES finder tool.
ADCES and danatech curate product specifics and periodically review them for accuracy and relevance. As a result, the information may or may not be the most recent. We recommend visiting the manufacturer's website for the latest details if you have any questions.