December 20, 2005
Insulin
Question from Hendersonville, North Carolina, USA:
In the past, pre-Humalog days, per approved instructions from Lilly and my physician, I would pre-mix Regular insulin with my NPH in the vial. In those days, it was standard treatment procedure to take a single daily injection. Today, I pre-mix Regular and Humalog insulins at 25%, 50%, 75% and 10% (Humalog with Regular). I also keep a vial of 100% Humalog for times when my blood sugar is high and needs to be lowered promptly. I use the appropriate mixture based on my pre-injection blood sugar test, planned dietary intake, and anticipated exercise. I combine these pre-mixed, fast-acting insulins with Ultralente (will have to go back to NPH next year) in pre-breakfast and pre-supper injections and independent of Ultralente for pre-lunch injections. The reason for pre-mixing is to simplify preparation for injection and to avoid dulling the needle by inserting it into multiple bottles of insulin. I’ve been doing this for years, therefore, I am confident in the effectiveness of this procedure. Is it necessary to shake the pre-mixed vials of fast-acting insulins with each injection, as required for the slow-acting insulins which separate in the vial, or will they combine with a single shake after mixing and not require shaking with each withdrawal from the vial?
Answer:
I would recommend shaking or rolling gently. This is also recommended for the commercially prepared pre-mixed insulins. The insulins do not remain homogenous solutions after being stored on the shelf. It would be very important to mix them. However, I am not sure that mixing in the vial is the best way to get the desired effect. It is likely that there is greater precision and less variability with mixing in the syringe.
JTL
[Editor’s comment: You may wish to discuss the use of Lantus as your basal insulin. In general, Lantus must be administered as a separate injection.
BH]
