Humalog Pen Information
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Questions About Using the Original Humalog & Humalog Mixtures Prefilled Pen
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How do I prepare my Humalog Mixtures Prefilled Pen?
A pen containing mixture insulin should be carefully rolled 10 times and inverted 10 times to completely mix the insulin. The insulin should look uniformly cloudy or milky after rotating. If not, repeat the step above until the contents appear uniformly cloudy or milky. Do not use if the insulin substance (the white material) remains at the bottom of the cartridge after mixing. Do not use if solid white particles stick to the bottom or wall of the cartridge, giving it a frosted appearance. Do not use if there are clumps in the insulin after mixing.
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Insulin does not come out of the needle. What should I do?
To obtain an accurate dose, you must always:
  1. Attach a new needle every time you inject
  2. Push in the injection button completely each time you inject (even if a 0 appears in the window) until a diamond or arrow is seen in the center of the dose window
  3. Prime the Pen prior to every injection and each time you use a new needle
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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.

If you have pressed the injection button and the dose was set too low, do not change the dose setting until the injection button has been fully depressed. After you have completed this injection, set a dose that is equal to the amount of insulin you did not receive and inject again.

If you have pressed the injection button and the dose was set too high, do not complete the injection. Remove the needle from your skin and dispense the remaining dose into an appropriate waste container. Contact your healthcare professional for further instructions.
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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 must not be used for measuring the insulin dose. Always look at the number in the dose window to determine your exact dose. Remember, when you dial your dose, you will not be able to dial more insulin than remains in the Pen.
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Why do I have to hold the injection button down for five seconds after the injection?
After the injection button is fully depressed, it takes a few seconds to completely expel the insulin dose, primarily due to the elasticity of the rubber plunger. As with all Lilly insulin pens, five seconds is recommended as the appropriate time needed to ensure full dose delivery.
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I dialed below the zero or beyond the 60-unit mark. Is the Prefilled Pen still usable?
The Pen is broken. You will have to use a new Pen.
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A small amount of insulin remains in the cartridge, but a dose cannot be dialed. Why?
Even though the Pen has delivered 300 units, a small amount of insulin will remain in the cartridge. This insulin cannot be delivered, therefore a dose cannot be dialed on the Pen.
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How many units of insulin are in the insulin cartridge?
There are approximately 320 units of insulin in the 3 ml insulin cartridge contained in a Pen. This includes 300 units of deliverable insulin, approximately 12 units of "overfill" (to ensure that each cartridge is capable of delivering the claimed 300 units), and approximately 8 units of insulin that is undeliverable and will remain in the cartridge.
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Why should I prime my Prefilled Pen?
Priming the Pen is required to maintain dose accuracy, and consists of an initial priming of a new Pen and priming prior to each dose. Initial priming brings the lead screw in contact with the plunger, fills the needle with insulin, ensures a fluid path, and removes most air bubbles that may be present in a new cartridge. Priming prior to each dose maintains the contact between the lead screw and plunger, fills the new needle with insulin to ensure a fluid path, and removes any air that may have entered the cartridge during storage or installation of a new needle.
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What is the approximate volume/amount of insulin used in the process of priming a Prefilled Pen?
The approximate amount of insulin used in the process of priming a Prefilled Pen is 2 units. When using a new insulin cartridge or Pen, the priming step may need to be repeated multiple times.
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Are air bubble(s) in my Prefilled Pen a problem?
A large air bubble or a cluster of bubbles may cause you to inject the wrong amount of insulin. However, a small air bubble is not a problem and will not affect the dose accuracy or injection time.
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How do I remove and/or prevent air bubble(s)?
Air bubbles should be removed by priming the Pen prior to injection. Priming is the most important step in making sure your insulin is delivered correctly and accurately. Priming ensures that:
A small air bubble may remain after completion of the priming step. If you have properly primed the Pen as instructed in the Pen User Manual, this small air bubble will not harm you or affect the dose accuracy.

In addition, needles should be removed from the Pen once the dose has been injected to prevent air bubbles from forming in the cartridge. Please refer to the Pen User Manual enclosed in the Pen box for further information.
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The dose numbers are not centered in the window. Is this a problem?
The Humalog, Humalog Mix75/25, and Humalog Mix50/50 Pen's dialing mechanism provides for a distinctive position as each unit is dialed. To get an accurate dose, you should attempt to center the numbers in the dose window before injection.
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What should I do with used needles?
Most states require that you store used needles in a hard container. An empty liquid detergent bottle or sharps containers are good examples. You can buy sharps containers at most pharmacies. Check with your local health department to confirm the rules where you live.
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Humalog, Humalog Mix75/25, and Humalog Mix50/50 are available by prescription only. See Humalog, Humalog Mix75/25, and Humalog Mix50/50 Patient Information and the User Manual enclosed in the Pen box for important facts about these products.

Important Safety Information
Humalog, Humalog Mix75/25, and Humalog Mix50/50 are for use in patients with diabetes to control high blood sugar. Humalog should be used with a longer-acting insulin, except when used in combination with sulfonylureas in patients with type 2 diabetes.

Humalog insulins are contraindicated during episodes of hypoglycemia and in patients sensitive to Humalog or one of its excipients. The safety and effectiveness of Humalog in patients less than 3 years of age have not been established. Safety and effectiveness of Humalog Mix75/25 and Humalog Mix50/50 in patients less than 18 years of age have not been established. There are no clinical studies of the use of Humalog insulins in pregnancy or nursing mothers.

Potential side effects associated with the use of all insulins include low blood sugar, weight gain, low blood potassium, changes in fat tissue at the site of injection, and allergic reactions, both general and local. Humalog Mix75/25 and Humalog Mix50/50 should not be mixed with another insulin. Starting or changing insulin therapy should be done cautiously and only under medical supervision.

Humalog insulins are available by prescription only. See the Humalog, Humalog Mix75/25, and Humalog Mix50/50 Patient Product Information for important facts about these products.

Humalog is a registered trademark of Eli Lilly and Company. Humalog Mix75/25 and Humalog Mix50/50 are trademarks of Eli Lilly and Company.



Humalog Patient Information | Humalog Mix75/25 Patient Information | Humalog Mix50/50 Patient Information | Important Safety Information