Explaining active insulin

True or false? Active insulin is a type of insulin that is out-going, heavily involved in sports and enjoys outdoor activities. False, it's actually an interesting and really important insulin pump feature included in the Bolus Wizard feature of our insulin pumps! 

If you use the Bolus Wizard and you're still not sure what active insulin is or how it's calculated, this blog is for you. Have you ever noticed that you tried to bolus insulin through the Bolus Wizard, and it changed the estimated amount of insulin you need? This is because of "active insulin." 

Let's start off with a word problem. What is the estimated total amount of insulin that will be delivered by your pump if you entered in a blood glucose of 200 with 60 grams of carbs with background settings of a 1:10 carb ratio, a 100 BG target, and an insulin sensitivity of 50? If you said 8 units of insulin, you'd be right...unless you still have 2 units of insulin in your body from a previous bolus. Then you only need 6 units of insulin instead of 8. As you know, this can make a big difference in your blood glucose. Those 2 units from your last bolus - that's active insulin. This feature is able to change bolus recommendations in cases like this one, when you might have insulin active in your system from a previous bolus. (This also could help if you already bolused for a meal and simply forgot that you did.) It's like it says, "Wait a minute? I just gave you insulin a couple of hours ago and I'm still working here so can you please not add any more insulin in here to make a correction to your high BG? Thanks." 

The fact that your pump tracks active insulin is a pretty cool safety feature. If the Bolus Wizard calculator recommends that you give a reduced amount of correction insulin or no correction insulin, it's because you have active insulin remaining from a previous bolus . There's a term known as "stacking" (and I'm not talking pancakes here). If you have ever heard of stacking, it's no laughing matter. It's injecting another dose of insulin too soon after a previous dose, resulting in low blood sugar. Active insulin not only allows for more accurate dosing, it helps prevent "stacking" of insulin which could lead to hypoglycemia. 

So what happens if you enter in your BG readings and carbs into you Bolus Wizard and it recommends less than you anticipated? Well, before you send your Bolus Wizard off to a math tutor, go into your status screen, check to see if you have active insulin on board, and take that into account.

IMPORTANT SAFETY INFORMATION

- Medtronic Diabetes insulin infusion pumps, continuous glucose monitoring systems and associated components are limited to sale by or on the order of a physician and should only be used under the direction of a healthcare professional familiar with the risks associated with the use of these systems. - Successful operation of the insulin infusion pumps and/or continuous glucose monitoring systems requires adequate vision and hearing to recognize alerts and alarms.

Medtronic Diabetes Insulin Infusion Pumps

- Insulin pump therapy is not recommended for individuals who are unable or unwilling to perform a minimum of four blood glucose tests per day. - Insulin pumps use rapid-acting insulin. If your insulin delivery is interrupted for any reason, you must be prepared to replace the missed insulin immediately.

Medtronic Diabetes Continuous Glucose Monitoring (CGM) Systems

- The information provided by CGM systems is intended to supplement, not replace, blood glucose information obtained using a home glucose meter. A confirmatory fingerstick is required prior to treatment. - Insertion of a glucose sensor may cause bleeding or irritation at the insertion site. Consult a physician immediately if you experience significant pain or if you suspect that the site is infected. For more information, please visit MedtronicDiabetes.com/isi.