Premixed Insulin

What is premixed insulin?

Insulin that comes in pre-mixed formulations combines insulins that have different onsets (how quickly they begin to work) and durations (how long the effects last) to best manage the blood glucose levels of the individual. Rapid-acting insulins work well for the increase in blood glucose that occurs right after meals, while longer-acting insulins help maintain blood glucose levels between meals and overnight. Many patients like pre-mixed insulins as they help reduce the number of injections needed per day, however they are not convenient for intensive insulin regimens. A person with diabetes may need to change their insulin regimen if they experience changes in their physical activity, weight gain or loss, increased stress, illness, or a change in diet. Changes like these should be discussed with a healthcare professional. Always check with your healthcare professional about any potential drug interactions before starting treatment and report any side effects you experience.

Some of the long-acting insulins available in the US include:

What is Humalog Mix 50/50 (50% insulin lispro protamine suspension and 50% insulin lispro injection)?

Humalog Mix 50/50 is a mix of 50% of a rapid-acting insulin (insulin lispro) and an intermediate-acting insulin (insulin lispro protamine suspension) used to treat adults with diabetes for the control of blood sugar. The rapid-acting insulin goes to work quickly in about 15 to 30 minutes, stimulating the cells to absorb glucose for their energy needs, while the intermediate acting insulin reaches its peak effect 2 to 4 hours after injection and continues working for up to 22 hours.* In addition to stimulating the absorption of glucose, insulin promotes the storage of glucose in the form of glycogen in the liver, stops the liver from producing more glucose, and promotes the conversion of excess glucose into fat. Humalog Mix 50/50 is available in vials and in prefilled pens (Humalog Mix 50/50 KwikPen). Once the pen is in use, it is good for 10 days and should not be refrigerated but stored at room temperature (below 86°F). The vial is good for 28 days after first use, and can be stored in the refrigerator or at room temperature. It is injected under the skin (subcutaneously) in the stomach area, upper arm, upper leg, or buttocks, usually within 15 minutes before a meal. Injection sites should be rotated to prevent thickening of the skin.

Some of the most common side effects experienced by people taking Humalog Mix 50/50 are hypoglycemia (low blood sugar), serious allergic reactions (including difficulty breathing, a rapid heartbeat, or sweating), reactions at the injection site (redness, swelling, and itching), and skin thickening or pitting at the injection site (lipodystrophy). Some people have experienced serious side effects with Humalog Mix 50/50 including heart failure and swelling of the hands and feet (edema). People who are experiencing episodes of hypoglycemia or who are allergic to any of the ingredients in Humalog Mix 50/50 should not use Humalog Mix 50/50.

What is Humalog Mix 75/25 (75% insulin lispro protamine suspension and 25% insulin lispro injection)?

Humalog Mix 75/25 combines 75% of the intermediate-acting insulin (insulin lispro protamine suspension) and 25% of the rapid-acting insulin (insulin lispro) to manage blood sugar in people with type 2 diabetes. The insulin in Humalog Mix 75/25 helps manage blood glucose levels by stimulating the cells in the body to absorb glucose. The fast-acting insulin usually begins working within 15-30 minutes after injection, while the intermediate acting insulin starts 2 to 4 hours after injection and lasts for 18 to 24 hours.* Humalog Mix 75/25 is available in vials and in prefilled pens (Humalog Mix 75/25 KwikPen) and should be injected subcutaneously in the stomach area, upper arm, upper leg, or buttocks, usually within 15 minutes before a meal. People using insulin injections are advised to rotate injection sites with each dose to prevent thickening of the skin.2 Once the KwikPen is in use, it is good for 10 days and should not be refrigerated but stored at room temperature (below 86°F). The vial is good for 28 days after first use, and can be stored in the refrigerator or at room temperature.

Some of the most common side effects experienced by people taking Humalog Mix 75/25 are hypoglycemia, serious allergic reactions (including difficulty breathing, a rapid heartbeat, or sweating), reactions at the injection site (redness, swelling, and itching), and skin thickening or pitting at the injection site. Some people have experienced serious side effects with Humalog Mix 75/25 including heart failure and swelling of the hands and feet. Some people should not use Humalog 75/25, such as people who are experiencing episodes of hypoglycemia or those who are allergic to any of the ingredients in Humalog Mix 75/25.

What is Humulin 70/30 (70% human insulin isophane suspension and 30% human insulin injection [rDNA origin])?

Humulin 70/30 has 70% of an intermediate-acting insulin (insulin isophane suspension) and 30% short acting insulin to help people with type 2 diabetes manage their blood sugar. Humulin 70/30 usually begins working within 30 minutes and continues to work for 18 to 24 hours.* Humulin 70/30 is available in vials or prefilled pens and should be injected subcutaneously in the skin of the abdomen, thigh, upper arm, or buttocks, usually 30 to 45 minutes before a meal. Each injection should be given in a different location on the body than the previous dose to reduce the risk of the skin becoming thickened.3 Once the prefilled pens are in use, it is good for 10 days and should not be refrigerated but stored at room temperature (below 86°F). The vial is good for 31 days after first use, and can be stored in the refrigerator or at room temperature.

Some of the most common side effects experienced by people taking Humulin 70/30 are allergic reactions (including redness, swelling, and itching at the site of injection or difficulty breathing, rapid heartbeat, and sweating), swelling in the hands or feet, weight gain, thickened skin at the injection sites, hypoglycemia, and hypokalemia (low potassium levels, which can cause fatigue, muscle weakness, and heart palpitations). Humulin 70/30 should not be used by people who are experiencing episodes of hypoglycemia or who are allergic to any of the ingredients in Humulin 70/30.

What is Novolin 70/30 (70% NPH, human insulin isophane suspension and 30% regular, human insulin injection (recombinant DNA origin))?

Novolin 70/30 is a mix of 70% intermediate-acting insulin and 30% short acting insulin. It is used in people with type 2 diabetes to help manage blood glucose levels. Novolin 70/30 begins working 30 minutes after injection and continues to work for up to 24 hours after injection.* Novolin 70/30 is administered via a vial and a syringe. Novolin 70/30 should be injected into the skin on the upper legs, upper arms, buttocks, or abdomen, usually 30 to 45 minutes before a meal. The injection site should be rotated for each dose. The vial is good for 42 days after first use, and should be only stored at room temperature once its opened.

Some of the most common side effects experienced by people taking Novolin 70/30 are hypoglycemia, reactions at the injection site (including redness, swelling, and itching), skin thickening or pitting at the injection site, swelling of the hands or feet. Rarely, people taking Novolin 70/30 have experienced serious side effects, including severe allergic reactions (including shortness of breath, rash over the whole body, rapid heartbeat, and sweating), heart failure, and hypokalemia. People who are experiencing episodes of hypoglycemia or who are allergic to any of the ingredients in Novolin 70/30 should not take Novolin 70/30.

What is Novolog Mix 70/30 (70% insulin aspart protamine suspension and 30% insulin aspart injection (rDNA origin))?

Novolog Mix 70/30 provides a mix of 30% rapid-acting insulin (insulin aspart) and 70% intermediate-acting insulin (insulin aspart protamine)to help control blood glucose levels in people with diabetes. Novolog Mix 70/30 begins working in 10-20 minutes and lasts for up to 24 hours.* The two different types of insulin help manage blood sugar during periods of fasting as well as after meals. Novolog Mix 70/30 is injected under the skin of the upper arm, upper leg, abdomen, or buttocks, usually within 15 minutes before a meal. As with any insulin injection, the site of injection should be rotated for each dose. Novolog Mix 70/30 is available in a vial for use with syringes or a prefilled pen (Novolog Mix 70/30 FlexPen®).5 Once the pen is in use, it is good for 14 days and should not be refrigerated but stored at room temperature (below 86°F). The vial is good for 28 days after first use, and can be stored in the refrigerator or at room temperature.

Some of the most common side effects experienced by people taking Novolog Mix 70/30 are hypoglycemia, allergic reactions, local injection site reactions, thickening or pitting of the skin at the injection site, rash, and itching. People who experience difficulty breathing, a rash over their whole body, and rapid heartbeat should seek immediate medical attention. Novolog Mix 70/30 may cause hypokalemia or severe allergic reactions. People who are experiencing periods of hypoglycemia or who are allergic to any of the ingredients in Novolog Mix 70/30 should not use Novolog Mix 70/30.5 *

*The times listed for onset, peak and duration of action are the usual values, however, these values can be highly variable for each patient.

Last Reviewed: April 2017
Last Edited: April 2017

Written by: Emily Downward | Last reviewed: April 2017
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