You can use a syringe, an insulin pen, or an insulin pump to take insulin. Insulin comes in a bottle (vial) or in an insulin pen.

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Before You Leave the Pharmacy and Each Time You Give an Insulin Injection:

Check to make sure you have the right type of insulin. Check the expiration date. Check the look of the insulin (appearance). It should be clear. Check that you have the right form of insulin. This means the insulin could come in a vial, disposable pen, or cartridge.

Throw Away Insulin and Use a New Vial, Pen, or Cartridge if:

Insulin has been left where it is very hot or very cold.

Insulin is cloudy or contains particles.

It is later than the expiration date on the vial, pen, or cartridge.

It has been more than 28 days since you began using the vial, pen, or cartridge.

Put a label on your pen, vial, or cartridge with date opened.


Insulin vials have U-100 insulin. That means there are 100 units of insulin in each milliliter (mL) of insulin. Humalog® insulin comes in 3 mL (300 units) vials or 10 mL (1000 units) vials. All other types of insulin come in 10 mL (1000 units) vials. Insulin pens or cartridges come in boxes of five 3 mL pens or cartridges.

Insulin Syringes

Insulin syringes come in three different sizes. The size of the syringe depends on your insulin dose.

Insulin Dose Syringe Size
Less than 30 minutes 0.3 ml (30 units)
30 to 50 units 0.5 ml (50 units)
51 units or more 1 ml (100 units)

Insulin Pens

There are two types of insulin pens:

Disposable Pens- most types of insulin are available in a disposable pen. They give full unit doses. You throw these away after all the insulin is gone.


Reusable Pens- These pens can be filled with Humalog® and Novolog® insulin cartridges. They can give ½ unit doses and can be used over and over again.


Syringes and needles come in different thickness and lengths. The doctor will prescribe the size for you.

‘Gauge’ means the thickness of the needle. The higher the number means the thinner the needle.

Needle lengths include: ½ inch (12.7 mm), 5/16 inch (8 mm), 3/16 inch (5 mm), and 5/32 inch (4 mm). Your healthcare team will tell you the needle length that is best for you. When using an insulin vial with U-100 insulin, you need to use an insulin syringe that says “For use with U-100 insulin.”


How do I Store Insulin?

Insulin Before opening After opening
Vial Store in refrigerator. Good until expiration date on vial. Store at room temperature. Throw away 28 days after first use.
Levemir insulin pen Store in refrigerator. Good until expiration date on insulin pen. Store at room temperature. Throw away 42 days after first use.

Humalog, Novolog, or Lantus insulin pen or Humalog or Novolog insulin cartridge

Store in refrigerator. Good until expiration date on insulin pen or cartrige. Store at room temperature. Throw away 28 days after first use.

*Source: These are the manufacturer’s recommendations.

When storing insulin in the refrigerator, the temperature should be between 36 degrees F and 46 degrees F. When storing insulin at room temperature, temperature should be between 36 degrees F and 86 degrees F.

Insulin Pump Therapy

Insulin pump therapy is basal and bolus insulin therapy. An insulin pump is a small device that gives you rapid-acting insulin (Novolog®, Humalog®, or Apidra®) all the time. This is the basal and bolus insulin.


The user can give a bolus dose of rapid-acting insulin when needed. This is for carbohydrates eaten and for bringing high blood glucose back to target.

A small flexible tube (cannula) is inserted under the skin to give the insulin. This is the infusion set. You or a family member needs to change the infusion set every 2 to 3 days.

Insulin pump therapy is not the right choice for everyone. The healthcare providers at the Diabetes Center want you to think about the following things before starting insulin pump therapy:

For the school age or older child, both the parent and child must want an insulin pump and be willing to learn about insulin pump therapy.

For the younger child, the parent must be willing to learn about insulin pump therapy.

You must go to clinic visits every 3 months.

You must be willing to check blood glucose at least 4 times a day.

You must look for blood glucose patterns to manage diabetes.

You must have good carbohydrate counting skills.

The family must be comfortable with basic diabetes management skills.

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If you think you might want insulin pump therapy, talk with your healthcare provider to decide if it is a good choice. We offer classes to make it easier to start insulin pump therapy. Here at Nationwide Children’s Hospital, we recommend you stay on shots (injections) for at least six months before thinking about insulin pump therapy. Your doctor and educator want to make sure that you have a good understanding of basic diabetes care. You also need to be comfortable with the injections and calculating your insulin doses. If the pump does not work, then you must be able to go back to injections and insulin dose calculations.