Questions About Using the Original Prefilled Pen
Insulin does not come out of the needle. What should I do?
I dialed the wrong dose (too high or too low). How do I correct the problem?
How much insulin is in the Pen?
I am not sure how much insulin remains in the cartridge. How do I determine this?
What should I do if my full dose cannot be dialed?
A small amount of insulin remains in the cartridge, but a dose cannot be dialed. Why?
Insulin does not come out of the needle. What should I do?
To obtain an accurate dose, you must:
- Attach a new needle.
- Push in the injection button completely (even if a 0 is seen in the window) until a diamond (♦) or an arrow (→) is seen in the center of the dose window.
- Prime the Pen.
Note: You may need to prime a new Pen up to six times before a stream of insulin appears.
I dialed the wrong dose (too high or too low). How do I correct the problem?
If you have not pushed in the injection button, simply turn the dose knob backward or forward to correct the dose.
How much insulin is in the Pen?
Each Pen contains a 3 mL (100U/mL) cartridge, which is filled with enough insulin to ensure the delivery of 300 units.
I am not sure how much insulin remains in the cartridge. How do I determine this?
Hold the Pen with the needle end pointing down. The scale on the clear cartridge holder (20 units between marks) shows an estimate of the number of insulin units remaining. These numbers should not be used for measuring an insulin dose.
What should I do if my full dose cannot be dialed?
The Pen will not allow you to dial a dose greater than the number of insulin units remaining in the cartridge. For example, if you need 31 units and only 25 units remain in the Pen, you will not be able to dial past 25. Do not attempt to dial past this point. (The insulin that remains is unusable and not part of the 300 units.) If a partial dose remains in the Pen you may either:
- Give the partial dose and then give the remaining dose using a new Pen, or
- Give the full dose with a new Pen.
A small amount of insulin remains in the cartridge, but a dose cannot be dialed. Why?
The Pen design prevents the cartridge from being completely emptied. The Pen has delivered 300 units of usable insulin.
What should I do if I cannot completely push in the injection button when priming the Pen or injecting a dose?
- Needle is not attached or is clogged.
- Attach a new needle.
- Push in the injection button completely (even if a "0" is seen in the window) until a diamond (♦) or an arrow (→) is seen in the center of the dose window.
- Prime the Pen.
- If you are sure insulin is coming out of the needle, push in the injection button more slowly to reduce the effort needed and maintain a constant pressure until the injection button is completely pushed in.
Why do I need to prime a new Pen up to six times?
The first time you use a new Pen, priming up to six times may be needed to see a stream of insulin come out of the tip of the needle. If you do not prime until you see a stream of insulin, you may get too much or too little insulin.
How and where should I store my Pen?
- Pens that have not been used should be stored in a refrigerator but not in a freezer. Do not use a Pen if it has been frozen.
- After a Pen is used for the first time, it should NOT be refrigerated but should be kept at room temperature [below 86°F (30°C)]and away from direct heat and light.
- Do not store the Pen with the needle attached. Doing so may allow insulin to leak from the Pen and air bubbles to form in the cartridge. Additionally, with suspension (cloudy) insulins, crystals may clog the needle.
- Keep the Pen and needles out of the reach of children.
Humalog Pens should be discarded 28 days after first use. Humalog Mix75/25 and Humalog Mix50/50 Pens should be discarded 10 days after first use. Be sure to also check the expiration date printed on the Prefilled Pen's label. The date must allow enough time for you to use all the insulin in the Pen.









