Insulin 102

This is a follow up to last week’s blog, if you haven’t yet, make sure you read it first here!

Now that we have talked about what insulin is, how it works and why Type 1 diabetics need to inject it, I realized there is much more info than fit in one blog post! Since insulin is what Type 1 diabetes revolves around, you never can learn too much about it, it’s a key to understanding life with Type 1.

Insulin has come a long way in the last 100 years. In 1920, Fredrick Banting and Charles Best were the first to figure out how to isolate insulin and successfully inject it to treat Type 1 diabetes. The first insulins was taken from cows and then from pigs. These insulins sometimes caused allergic reactions and the volume needed to be injected was huge. It also needed to be injected into a vein which developed scar tissue making it difficult to continue finding new veins to use. And the insulin rarely could bring blood sugar back into the normal range of a non-diabetic and many still died younger from complications.

In the late 1970s, the first synthetic insulins were developed which were closer to human insulin. They also could be injected in any fatty tissue without needing to find a vein. The volume required to inject also went down to about 1/4 of what was needed previously. The development of these synthetic insulins greatly improved the quality of life and lengthened Type 1 average life span to nearly normal.

Advances in synthetic insulins continued, eventually leading to what are now the most commonly used insulins, Humalog and Novalog (and their counterpart long lasting basal insulins). These have been the most stable insulins yet, releasing at a steady and predictable rate and the closest at mimicking human insulin made in the pancreas. There continue to be new insulins that come out, including a new fast acting insulin called Fiasp which starts working within 10 minutes instead of the standard 20. There is also inhaled insulin (although not suitable for all diabetics or all situations) and additional methods besides injecting being studied. Insulin can not be taken orally as it is broken down by the stomach acids and never makes it to the bloodstream.

Insulin must be kept refrigerated. Once a vial of insulin is allowed to reach room temperature, it must be used within 30 days before it goes “bad”. Old insulin isn’t harmful, it just won’t work. Like pretty much all Type 1 diabetics, I go through more than 1 vial of insulin each month so once I open a new vial, I put it with my backup infusion set in my purse. That way if I have a pump failure, I have insulin with me (along with a couple of syringes). But I also have to make sure I don’t leave my purse in a hot car as letting insulin get too hot also makes it go bad!

These synthetic insulins have a very distinct chemical smell instantly recognizable to any Type 1 diabetic. I have become somewhat desensitized to the smell over the years, I’ve been told my room sometimes smells of insulin (where I do most of my pump refills) but I don’t smell it. Sometimes insulin spills happen and getting any insulin on my hands can take a day or two to clear (even with washing them). If you ever want to know what insulin smells like, pretty much any Type 1 diabetic can pull out a vial or pump and give you a whiff. It’s not the worst smell but not pleasant either!

A vial keeper has become a popular accessory for anyone who uses insulin. I have heard many horror stories of an expensive vial of insulin breaking and spilling all its contents! In my 14 years of being diabetic, I have never broken a vial of insulin! I have dropped one a time or two but never broken one. I do not own or use a vial keeper as I still feel relatively confident that I don’t need one. Maybe one day life will prove me wrong!

Insulin is measured in units, a system of measurement not used for any other injectable medication. Type 1 diabetics have multiple ratios and sometimes need a math degree to determine how many units are needed for any given situation. There is a carb ratio (for example 1 unit of insulin per 10 carbs) but there is also a correction ratio for high blood sugar and a basal insulin ratio. Insulin pumps can also now dose insulin in .10 of a unit adding fractions to the math. Thankfully technology has advanced and can do most of the math for the diabetic. But if you want to sound really smart, the next time you see a diabetic injecting insulin (either with a pump or syringe), ask how many units they are injecting ?

Insulin is used for Type 2 diabetics when oral medications, diet and exercise still isn’t enough to keep blood sugar in range. After many years of being a Type 2 diabetic, the stress can cause their pancreas to stop producing enough insulin. But almost all Type 2 diabetics still make some of their own insulin in their pancreas and won’t die nearly as quickly without injecting it as a Type 1 diabetic will. Insulin use is one area where Type 1 and Type 2 diabetes treatment can overlap but the similarities are small and the differences are still huge.

So now that you are becoming an expert in everything insulin, you might be wondering about the recent hype over insulin prices. But since that is a whole new can of worms, you will have to come back next week to read about the controversy and my opinion about it…

Leave a Reply