Insulin Administration Guidelines

Rationale for Separate Administration

Insulin glargine (Lantus) should not be mixed with other forms of insulin, including Novolog 70/30, due to the low pH of its diluent which can affect the pharmacokinetics of other insulins 1, 2, 3
When mixed with other insulins, physicochemical changes can occur that alter the pharmacokinetic properties of both insulins, potentially leading to unpredictable glucose control 1, 2
The American Diabetes Association explicitly states that insulin glargine should not be mixed with other forms of insulin 1, 3

Basal insulins like Lantus may be used in combination with premixed insulins, but must be administered separately 4
Using only Novolog 70/30 twice daily (before breakfast and dinner) is a potential alternative regimen 4
Using Lantus once daily plus rapid-acting insulin (like regular Novolog) before meals is another potential alternative regimen 4

When switching between insulin regimens, maintain the same total daily dose initially but adjust the distribution appropriately 5
More frequent blood glucose monitoring is essential during any transition period between insulin regimens 5, 6

Never mix Lantus in the same syringe with any other insulin 1, 2
Avoid converting between insulin regimens on a 1:1 basis without considering appropriate dose adjustments 5, 6
Don't neglect more frequent blood glucose monitoring during transition periods between insulin regimens 5
Remember that meal timing becomes more critical with premixed insulins compared to basal-bolus regimens 5, 6