Humalog Pen Information
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Questions About Humalog & Humalog Mixture Insulins & Pens
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What should my Humalog look like?
Your insulin should be clear and colorless with a water-like appearance and consistency. Do not use if it appears cloudy, thickened, even slightly colored or has solid particles in it.
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What should my Humalog Mix75/25 or Humalog Mix50/50 look like?
Your insulin should have an even, cloudy appearance after gentle mixing/rolling. Do not use if there are clumps in the insulin after mixing. Do not use if particles on the bottom or wall give the vial a frosted appearance. If any of these conditions appear, contact the Lilly Answers Center at 1-800-LillyRx (1-800-545-5979).
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What kind of insulin is available in the Prefilled Pens?
In the United States, the Prefilled Pen is available in the following insulins: Humulin 70/30, Humulin N (NPH), Humalog, Humalog Mix75/25, and Humalog Mix50/50.
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What kind of insulin can be used in the Reusable Pens?
The HumaPen® MEMOIR™ and HumaPen® LUXURA™ HD can only be used with Humalog insulin cartridges.
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Do the Prefilled Pens require a prescription?
The Humalog, Humalog Mix75/25, and Humalog Mix50/50 Pens are the only Lilly Prefilled Pens that require a prescription. However, it is likely that your health insurance plan may require a prescription for reimbursement of any type of Pen, including Humulin 70/30 or Humulin N. Needles for your Pen also may require a prescription.
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Do the Reusable Pens require a prescription?
Yes, the HumaPen MEMOIR and HumaPen LUXURA HD require a prescription. Humalog insulin cartridges also require a prescription. Needles for your Pen also may require a prescription.
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How much insulin is in the Prefilled Pen?
The Humalog, Humalog Mix75/25, and Humalog Mix50/50 Pens are prefilled with at least 300 units of insulin.
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How much insulin do the Reusable Pens hold?
The HumaPen MEMOIR and HumaPen LUXURA HD are used with 3 mL Humalog insulin cartridges containing at least 300 units of insulin.
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What kind of needle can be used with the Prefilled and Reusable Pens?
The Pens are suitable for use with Becton, Dickinson and Company's insulin pen needles. There are a variety of pen needles available. You should consult with your healthcare professional to determine the size of the Pen needle appropriate for you.
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What is the maximum dose I can take at a time?
The Prefilled Pens and HumaPen MEMOIR can deliver up to 60 units of insulin at a single time. HumaPen LUXURA HD can deliver up to 30 units of insulin at a single time. However, it is important that you take your doses as directed by your healthcare professional.
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How and where should I store my Prefilled Pen?
Humalog, Humalog Mix75/25, and Humalog Mix50/50 Prefilled Pens should be stored in the refrigerator, but not in the freezer, until first use. The Pen currently in use should not be refrigerated but should be kept as cool as possible (below 86°F [30°C]) and away from direct heat and light. Do not use an insulin pen if it has been frozen. Do not store the Pen with the needle attached. Storing the Pen with the needle attached may allow insulin to leak from the Pen and air bubbles to form in the cartridge.

Humalog Pens in use should be discarded after 28 days. Humalog Mix75/25 and Humalog Mix50/50 Pens in use should be discarded after 10 days. 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 vial or pen. Do not buy or use insulin past the expiration date. You may also refer to the insulin storage chart at www.LillyDiabetes.com.
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How and where should I store my Reusable Pen?
The HumaPen MEMOIR and HumaPen LUXURA HD should never be placed in the refrigerator. Keep the Pen and case away from water, moisture, or wet surfaces as they are not watertight. Keep the Pen away from dust, extreme hot or cold (freezing) temperatures, and direct sunlight. Do not store the Pen with the needle attached. Storing the Pen with the needle attached may allow insulin to leak from the Pen and air bubbles to form in the cartridge. For your Humalog insulin cartridges, refer to the Patient Product Information for complete storage instructions. Be sure to also check the expiration date printed on the cartridge label.
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If my Prefilled Pen or Reusable Pen gets immersed in water, is it still okay to use?
Any Pen that has been immersed in water should not be used.
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How long will my insulin work?
How long the insulin will last may vary in different individuals or at different times in the same individual, based on dose, site of injection, blood supply, temperature, and physical activity. In general, the type of insulin will tell you how fast it starts to work and how long its action continues. Humalog is a rapid-acting insulin, so it starts lowering your blood sugar more quickly, and has a shorter duration of action compared to regular human insulin. Humalog Mix75/25 and Humalog Mix50/50 are longer-acting insulins combined with the more rapid onset of action of Humalog. Please see the Types of Insulin page for a chart showing the time activity of Humalog and Humalog Mixture insulins.
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My vial of insulin is "bubbling or foaming" more than usual. There are lots of bubbles. Is it safe to use?
Insulin has surface activity; it behaves like a very diluted soap solution. Agitation causes foaming. During in-use studies that simulated patient dosing regimens, there has been no evidence that foaming affects the stability of the insulin. If the solution or suspension appears normal as described in the package insert enclosed with your insulin vial, then it should be safe to use. Care should be taken not to inject air from the syringe (to equalize pressure) directly into the solution; inject the air before inverting the vial to take a dose. Injecting air directly into the solution could lead to bubble formation.
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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 Pen User Manual enclosed in the Pen box for important facts about these products.

HumaPen MEMOIR and HumaPen LUXURA HD are available by prescription only.

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