Whats your ISF/I:C?

I know everyone is different but I keep getting these swings of needing not very much insulin and then needing a lot and it is very frusterating.

Right now(this is one of those bad times) my I:C is 1:10-12 and ISF about 25. most of the time its more like I:C is 1:18 and ISF of 40-60 depending on time of day, activity and mood

So whats yours???

And is this swing norm??? It will be like a week of hell and a few weeks of norm

Ok, I’ll give you mine, but I’ll also ask a question.

My ICR is 5 and my ISF is 20, but I only stared insulin in December. My ICR is probably pretty close, but I’ve only really corrected I think twice, so who knows on my ISF.

So here is my question. Why does everyone call it an I:C ratio and then quote their C:I ratio (kudos to Adam for actually using a correct form)?

LOL, I’ve noticed that ratio issue too! I am running about 8-9 these days. I was at 7 last year for most of the year, changed to 6 after some highs @ lunch and then realized I was correction munching a lot. I decided to cut the nuts out of my diet, reasoning that some of the highs I was seeing might have been delayed fat processing and nudged it up to 7, then 8 and now am 9 and am still seeing fairly significant crashing after breakfast like 4-5 days/ week. I always have left breakfast a shade higher for DP attack purposes but seem to have my “basal bumps” programmed pretty correctly to cover that so I will probably get it a shade higher next week?

BSC - I don’t think everyone quotes it C:I - mine is breakfast: 1 unit of insulin to 7 of carbs, lunch 1 unit of insulin to 8 of carbs and dinner 1 unit of insulin to 18 of carbs, isn’t that insulin to carb??

Adam, have you done basal testing? If your basals are off than it’s hard to get your boluses right. Also, you might want to have different I:C ratios for the different meals, as it’s natural for it to be different at different times of day. Look at how different mine is for breakfast, lunch and dinner.

Also different things can affect your insulin needs. Do you exercise for example more or less at different times?

My I:C ratio is 1:10 and I take 2 units Levemir once a day. I am LADA and still in my honeymoon phase.

My ISF is 100. I:C is 1:20-25 for breakfast, depending on whether I plan to exercise right away, 1:20 for lunch, and 1:15-18 for dinner.

My I/C also decreases with each meal as the day progresses: breakfast - 1:5, lunch 1:10 and dinner 1:20

I posted a similar question some time ago, and didn’t get anyone who had seen the same thing.

In my case (T1 for 36 years), I have found that my C:I ratio can vary from one day to the next, and I haven’t found a way to predict which days will have which ratio. Besides the obvious things like being sick, I even changed from Lantus to Levemir in part because it has been reported to be more predictable (I didn’t really notice a difference). Its possible that basal injections are inherently more unstable than pumping, but I’ve never tried pumping so I don’t know. Bernstein seems to prefer basal injections to pumping, so that it at least one vote for basal injections being stable. I do believe that one thing that can affect it is you let your BG go high enough to go into the 200’s or above for more than a few hours - I believe that this can make you insulin resistant for at least a day. There are also reports that going low (say below 50) can make you insulin resistant for at least several hours.

But the biggest thing that can definitely have a big impact on insulin sensitivity is exercise. Are you changing the amount of exercise you are getting? Increasing exercise makes you more insulin sensitive, and will increase your C:I ratio.

By the way, by my computation C:I should generally be about 3.6 times ISF.

Since you were diagnosed less than a year ago it’s likely you’re coming out of your honeymoon a bit, so increases in insulin would be expected.

Seven units is not a lot of Lantus. It’s not uncommon for Type 1s to be on 15-30 units, although the dose of course varies, but seven or even ten units is a pretty small dose compared to average, I’d say.

For the OP, my I:C ratio is currently at 1:10, though this varies a lot depending on my activity level and hormones (ranging from 1:8 to 1:14 on average). My ISF is 1 unit per 2 mmol/L, which I pretty much never change, although I’ve wondered whether I should adjust it as I do with my I:C ratio and ISF in relation to exercise/hormones/etc.

Lynne, Yes, I’ve always taken two shots a day - with either Lantus or Levemir. Lantus didn’t last me 24 hours (I tested it because my DE wanted me to way back when I started on it when it first came out). I didn’t bother to test with Levemir since it is supposed to be shorter-acting than Lantus. I do take more Levemir than I did Lantus. Actually substantially more, but part of that seems to be that I’ve shifted a lot of what I used to bolus and now take it as basal. Also I’m not low-carb - I probably average between 150 to 200 g carb per day so don’t think it will be comparable to you.

Your TDD (total daily insulin dose) is far far less than mine. But I’m 6’5" and weigh 185 pounds and am long-term T1 so it is to be expected that my insulin requirement is much higher than yours. My current daily insulin intake (always subject to change) is averaging about 65 units a day. 50 units of that has been Levemir for the last couple months or so - I was at 40 units for several months before that but I worked my way up to 50 and that is working better. Sounds like a very high proportion of basal given my carb intake, but it is what it is.

Anyway from my experience the short answer is - no 10 (or 7) units of basal insulin is certainly NOT a lot. As long as it keeps your BG in a good place that’s really all that matters.

Lunch & Dinner: 1:8

ISF: 80

I know I am going to have to change that for tighter control on the pump. Once I get to where I want to be then I can change it again. But right now i am thinking that isn’t working for me.

I:C of 1:15 for breakfast and lunch, 1:18 for dinner.

ISF of 1:75

What is ISF?

Insulin sensitivity factor. How many points one unit of insulin lowers your blood sugar, used for correction purposes. Mine is about 1/40. One unit of insulin will lower my blood sugar 40 points.

How do you figure out your ISF?

A T1.5 LADA in honeymoon is likely to be very different, so I hesitate to give any recommendation.

The best way is to test - if your BG is high and you don’t have any active bolus insulin (and your basal is set correctly), then see how much a unit of bolus brings your BG down. That is your ISF. But if your pancreas is still working (LADA and honeymoon) then your BG may come down on its own, which makes your ISF harder to measure.

It can be guessed at using equations starting with TDD (total daily dose): the 1500 rule etc. But these are designed for T1 not in honeymoon. They are in the Using Insulin, Pumping Insulin, Think Like a Pancreas, etc. books and also can be found online.

You got it. But to get an accurate result you need to wait until all the rapid acting insulin has had a chance to complete its action - and that can take 4-5 hours. So your sensitivity is likely even bigger than 1:100. Next time assume a number larger than 100 and treat based on that; then hopefully it’ll settle down nicely without needing to treat with orange juice and after the four or so hours you’ll get an even more accurate number. As with all this diabetes stuff, it takes several attempts before you can settle on a number. (And then of course things change in a month so you have to do it all over again!)

People vary widely, partly because of eating and exercise habits, but also according to how much insulin resistance they have (yes, Type 1’s DO get insulin resistance – usually none to mild, but sometimes significant!)
In my case, my I:C ratio is 1:8, and my ISF is 30. I do have some mild insulin resistance, but according to my endo, I’m not far off the mark. And looking at the answers here, I am also reassured! :slight_smile:

I believe for my size and being a honeymooning LADA I am not very sensitive to insulin. My I:C ratio is only 1:8-10 so at my size, how much I exercise, and being in my honeymoon I would consider myself to have some insulin resistance which my endo said most LADAs are insulin deficient AND resistant and I believe I fall into that category.

Thanks Jag. Yes I did read about this in Using Insulin but I believe it was called “testing your correction factor” so I was a little confused. I have not done this yet but don’t seem to be very sensitive to humalog.