In the spirit of Austin Powers, let’s talk about insulin and how it behaves in your body. Over and over again I come across people using insulin that don’t know the first thing about how to evaluate doses or how it behaves in their body. That could potentially lead to multiple problems. Too much insulin could create a hypoglycemic episode and not enough insulin could lead to hyperglycemia or even DKA (diabetic ketoacidosis). Understanding insulin can go a long way in preventing these highs and lows. Let’s take a look at this “international medicine of mystery”.
It's groovy to think that insulin just celebrated its 100th birthday in 2022. Prior to 1922 there was no treatment for T1D beyond food restriction. Even then, people only lived months as severe weight loss and DKA claimed lives. As early as the 1880’s, German researchers discovered that removing pancreases from dogs produced symptoms of diabetes and by 1910 further research identified that only one chemical was missing in the pancreas of people with diabetes. A British bloke named Sir Edward Albert Sharpey-Shafer called this chemical insulin! Moving forward to 1921, Dr. Banting figured out how to make a more pure form of insulin utilizing cattle pancreases. This insulin saved the life of Leonard Thompson in 1922, a 14 year old boy dying from diabetes in a Toronto hospital! This smashing new concoction saved Leonard’s life and countless millions to this day!
Though insulin from cattle and pigs saved lives, it had its bloody problems, namely allergic reactions. By 1982 Eli Lilly solved that issue by bringing the first biosynthetic human insulin to market. Insulin now comes in many forms giving people options as to how to treat their diabetes. However, “options” can sometimes equal confusion and not all insulins are created equal.
Let’s get switched-on and dive into the world of insulin. There are generally considered 6 different types of insulins: Rapid-acting, Short-acting, Intermediate-acting, Long-acting, Ultra-long-acting, and Premixed insulin. There is actually an inhaled insulin as well. Each are designed to work at different speeds and for varying durations. When starting insulin, make sure you know when your insulin starts working (onset), when does it have its most action (peak), and how long does it stay in your body (duration). Knowing/understanding what kind of insulin you are prescribed can go a long way in preventing dangerous lows and highs.
Rapid-acting insulin (meal time) is prescribed to cover the carbs in meals. Once given, it is ramping up in 15 minutes, peaking around 60-90 minutes, and stays active for up to 4-5 hours. I often have patients that don’t understand the importance of eating their meal within 15 minutes of dosing their rapid-acting insulin. One particular lass dosed her rapid-acting insulin and decided to drive her car pool route then go to a fast food restaurant for breakfast. Needless to say she ended up on the side of the road treating a low blood sugar. Thankfully she didn’t wreck her car, cause an accident, or hurt another person!
It gets more tricky when using the older insulins like Regular, NPH, or pre-mixed. You may need to dose your Regular insulin 30 minutes before eating and NPH peaks in 6-8 hours and can hang around in your body for up to 12 hours. Don’t skip meals when on these insulins to prevent hypoglycemia and often you have to plan your meal times/snacks when these insulins have their most action. The advantage to Regular/NPH insulins is that they are usually less expensive than newer insulins.
Long acting insulin generally does not have a peak and has a duration up to 24 hours (longer if it’s ultra-long-acting). This type of insulin does little to cover food. Instead, it is prescribed to control blood sugars between meals and through the night. This insulin is designed to release slowly throughout a 24 hour period to mimic what your pancreas would do if it could! We often call long-acting insulin your basal or background insulin. It sends the message to your liver that it does not need to share excess sugar in between meals and while you are sleeping. Two pro-tips to remember: take this type of insulin at the same time every day to maintain around-the-clock coverage and use your fasting or before meal blood sugar to evaluate your dose.
Insulin has come a long way baby! Research is still occurring and new insulins are on the way! Quicker onsets and shorter durations for rapid-acting insulin and there is a once weekly ultra-long-acting insulin approved in other countries, but still waiting on FDA approval in America. There is no better medication to lower blood sugar than insulin if you need it. As Austin Powers might say, “Don’t lose your mojo, baby”, understand your insulin and how it behaves.
- Stacey Fox BSN, RN is a Diabetes Nurse Educator for the University of Colorado Health system. She is the proud mom of Leah, founder of One2One Diabetes.