Formula For Taking a Shot

Does anyone know the formula for figuring out the amount of insulin you would take in a shot? My blood sugar has been high for about the last 4 days. I have changed my infusion set 4 times. I have just been doing an inordinate amount of insulin by bolusing, but its not helping. In fact, sometimes it goes up. I haven’t eaten anything since dinner last night and my BG right now is 368. I don’t want to just keep bolusing, but I don’t know the formula for doing a shot. I thought I would try that before calling my Dr. This is insane! I have had this happen before, but usually after changing the infusion set and insulin about 3 or 4 times it seems to straighten itself out. I’m so tired of this. I may need to go buy some strips and check ketones. Good Grief!

New Insulin/new bottle/new batch? If you get your insulin shipped to you, maybe it is not shipped properly?

Taking insulin by syringe would use the same formulas as your pump. Maybe use your pump to calculate. Shoot into your leg to get it to work faster?


I have had this issue also a couple of times in the past. I need to exercise in order to fix the problem. I guess this increases the absorbtion rate. I do this when all else fails (like changing infusion site, getting new insulin, correcting). By exercise, I mean hitting the gym. A fast walk won’t help me in this case. This is a very annoying problem for me, and I hate being annoyed and feeling crappy because of the high.

Hi Bobby,

Sounds like you’ve got some bad/ineffective insulin on your hands/in your veins. I would guess it’s lost it potency, judging by the fact you’ve changed infusions sets 4 times without positive results. I’d grab a new bottle of insulin and dose a shot.

(current BG - target BG) / correction factor = units insulin

Your pump should have your “correction factor” stored in a “pump settings” menu. It should say something to the effect that “1 unit of insulin will drop your blood glucose __ points mg/dl.” For me, 1 units drop my BG by 45 points mg/dl.

If your target blood glucose is 100 (like mine, for example), subtract that from your current BG value (368-100 = 268).

That’s the number of BG points you want to drop, so you’ll need to use this to calculate your shot. Divide the BG value drop by your correction factor. If it were me, it would be 268/45 = 5.96 units, which I’d round up to 6 units insulin (I use humalog).

If I used my settings, here’s the math:

(current BG - target BG) / correction factor = units insulin
(368 - 100) / 45 = units insulin
268 / 45 = units insulin
4.96 units insulin

To be safe, you might want to use a bit less insulin to start, and then track your BG as it drops. You can always give an additional shot of insulin, if needed. That way, you don’t rocket your BG back down to fast, possibly causing a bad hypo event. Good rule of them I learned is the higher the high, the more gradually you want to bring it back down.

Hope you get the BG level back to where it needs to be soon.
Cheers, Mike

Is it possible that you have an infection? I’ve had the experience when I didn’t know that I had an infection and I actually doubled my insulin delivery without significantly dropping my BG. Once I started on antibiotics the BG started to respond to insulin normally. If you suspect an infection you would be best off by seeing the doctor.

I’ve also heard that heart disease will throw BGs out of whack. I don’t mean to be an alarmist but if you’ve already ruled out a bad site by changing infusion sites and you’re confident that your insulin is good then you should consider other possibilities.

I’ve also found that a large percentage of fat in my diet upsets my BG control.

Good luck. I would be curious to know what you learn as you solve this problem.

4 days of high blood sugars? You need to contact your endocrinologist and also test for ketones. As others have mentioned, the correction factor is stored in your pump

You have the same pump as me…

Press ACT
go to BOLUS
Press ACT
press ACT
press ACT

next to SENSITIVITY… You will find how many points 1 unit will drop you … IE… 50/60… so on

if you have any questions Bobby, please send me a message, I’d be more than happy to help you :slight_smile: