Can I make insulin substitutions to control my blood sugar?

A fellow caregiver asked...

I am taking insulin injections to help control my diabetes. I am also in the donut hole with my Insurance company and their drug plan coverage. I am currently taking 60 units twice a day of Humalog 75/25 Mix. Would I be able to stop taking the Humalog 75/25 Mix and start taking Novalin 70/30 Mix? I'm on SS Disability and I get a 30 day supply of my insulin and other medications. I asked my family doctor but I am still waiting for a reply and I would like a second opinion with this matter.

Expert Answer

Theresa Garnero is clinical nurse manager of Diabetes Services at California Pacific Medical Center in San Francisco.

With your doctor's authorization you should be able to switch from 75/25 to 70/30. You may need an adjustment in the amount of units taken as the action profile is different (when your new insulin peaks - or is working at its strongest). This is important to know as your risk for lows with the 70/30 is slightly later (2 to 4 hours after injection)  than the risk for lows with the 75/25 (30 to 90 minutes after injection). In addition, working with a diabetes educator can help you fine tune your program within your insurance plan limitations.