# A question for those on MDI **URL:** \ **Category:** T1D Tech & Daily Management Support\ **Created:** [October 12, 2026, 10:46am UTC](https://forum.breakthrought1d.org/t/a-question-for-those-on-mdi/75242 "2026-10-12T10:46:30Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![wadawabbit](https://sea1.discourse-cdn.com/flex025/user_avatar/forum.breakthrought1d.org/wadawabbit/32/3890_2.png) [@wadawabbit](https://forum.breakthrought1d.org/u/wadawabbit)\ **Post date:** [October 12, 2026, 10:46am UTC](https://forum.breakthrought1d.org/t/a-question-for-those-on-mdi/75242/1 "2026-10-12T10:46:31Z")
I feel silly asking this question but it’s been so long since I’ve been on injections I don’t know the answer​😊. If you take shots, when dosing for meals so you use a sliding scale, or get as close as you can with a carb ratio? ---
**Author:** ![Dennis](https://sea1.discourse-cdn.com/flex025/user_avatar/forum.breakthrought1d.org/dennis/32/5527_2.png) [@Dennis](https://forum.breakthrought1d.org/u/Dennis)\ **Post date:** [October 12, 2026, 8:00pm UTC](https://forum.breakthrought1d.org/t/a-question-for-those-on-mdi/75242/2 "2026-10-12T20:00:59Z")
Dorie @wadawabbit , I don’t currently utilize management method currently known as MDI - originally referred to, as you may recall, as IGC or Intense Glucose Control. I used as close to exact as possible calculations rather than hit=or-miss pre-printed sliding scale that slides over two critical factors for proper insulin dosing. The formular we(\*) developed in its most basic written arithmetic format is A+B-C, which I calculated in my head, and which form the underlying theory of many dose calculators [such as in pumps] in use today. I’ll try to explain this formular: A = (BG-Target) / ISF [this value can be either negative or positive} B = Total Carbs x I:Cr C = Estimated bolus still active **NOTE “we(\*)”**: In 1975, I was recruited, or shall we say assigned, by the Medical Director of Joslin Clinic to work with a Joslin diabetes scientist in an attempt to develop better methods for diabetes management. Up to that period, insulin dosing by using a single daily injection (sometimes split into two half doses per day) of Long-Acting insulin [not to be confused with long0duration background formulations which became available in 2002 with Lantus] such as NPH or the just arrived Humulin-N. The success of our work was proven by the worldwide DCCT Study of the 1980s. ---
**Author:** ![spdif](https://sea1.discourse-cdn.com/flex025/user_avatar/forum.breakthrought1d.org/spdif/32/5548_2.png) [@spdif](https://forum.breakthrought1d.org/u/spdif)\ **Post date:** [October 12, 2026, 10:22pm UTC](https://forum.breakthrought1d.org/t/a-question-for-those-on-mdi/75242/3 "2026-10-12T22:22:53Z")
> ### Think Like a Pancreas > > Gary Scheiner, MS, CDCES > 4th ed., p. 182-183 > > #### Chapter 7 In Search of the Perfect Bolus > > There are many unusual factors that can influence bolus requirements; several will be covered in the next chapter. For our purposes here we will focus on the five primary factors that should be considered when determining bolus doses: > > 1. the amount of carbohydrates in the meal or snack > 2. the glucose level at the time of the meal or snack > 3. the direction the glucose is headed > 4. the amount of insulin still remaining from previous boluses > 5. the amount of planned (or recently completed) physical activity > > If you are into math (you know who you are - your favorite shows are _The Big Bang Theory_ and whatever the latest iteration of _Star Trek_ happens to be), boluses are calculated as follows: > > > **Bolus dose** = (food dose + correction dose + rate-of-change adjustment - insulin on board) x activity adjustment When I was on MDI earlier this year this is what I did, except I’d memorized the food doses so I didn’t use a carb ratio to math the food dose. Are you working on your what to do when your pump fails plan or got something else going on?