One Unit of Insulin is dropping me 90 points

I want to start this off by saying, I don’t think it’s my basal insulin. I have done the fasting test and my sugars are stable.

I recently had to change my basal insulin due to what I think is altitude change?
I am on 15u tresiba and at this point am doing 5u average novolog a day. I weigh 130lbs so this is kind of low right?

I have been type one for 11 years and just until recently was on 28u of lantus for most of my life.

Has anyone had an experience that’s similar?
I have stopped eating carbs out of fear at this point lol

Hi @ashlyn901.
I just want to make sure I’m understanding correctly: you recently switched from Lantus to Tresiba.

  • Basal rate checks look good for your new long acting insulin.
  • You take about 5 units Novolog during the day - divided as needed,
  • One unit of which drops you a whopping 90 points(!)

For process of elimination I’m wondering how your Novolog performed in conjunction with your Lantus - basically what was your ratio? I wonder (in my creative little mind) if there may be issues with certain combinations of long acting and bolus insulins. I use a pump and only occssionally go on shots - my combo works well for me so I’ve never thought about whether certain combinations might have particularly drastic effects.
I understand some individuals may start producing their own insulin even after taking it via shot or pump for a while - maybe you would call that a second honeymoon🤪??? There are tests that can determine if that’s the case.
If it were me, and just 1 unit of fast acting brought my numbers down so drastically, I would not give up the carbs but would see what happens if I ate them without taking a bolus/injection as I typically do.
Regarding your weight, think of it as a starting point to use as a guideline for what people on average - cough cough - need to start with. From there lifestyle and a number of other factors will inform any adjustments to get the best dosage for you.
I would definitely contact my doctor about this new development. If you are familiar with the site you may have seen the phrase “be your own doctor” - with experience we learn to make our own adjustments and tweaks without calling them frequently. But those changes don’t typically need to be dramatic so I would check with my endo to make sure all bases are covered.
Keep us posted!

1 Like

hi @ashlyn901 are you saying you have tested basal, by fasting, since changing to Tresiba? I am guessing that you have checked by skipping random meals and by your sugar overnight that you are not rising or dropping if you don’t eat.

so how did you test your insulin sensitivity? was it by CGM or by finger stick or something else? was it over a 4 hour duration?

All I could get on Tresiba is that it tends to be (and I am oversimplifying it here) “stronger” than Lantus, so 1 unit of tresiba is “more” than 1 unit lantus… I think because each shot adds to the last one (Tresiba has a half life of 25 hours versus Lantus half life of 12 hours) so the overall drop in units on tresiba is not really that scary… Tresiba also comes in much stronger concentrations you didn’t mention the U-value of the version of tresiba you were prescribed.

all that aside, if your sugar is not rising or falling between meals, if you are even slightly more active (if you live at high altitude now, are you sure you aren’t walking more, eating less fat, taking up mountain biking or x-country skiing for example)? Activity has a 10X factor in me… if I needed 10 units for some huge carb meal, I could drop it to as low as 1 unit depending on the type and duration of activity I was going to do next.

anyway all I got is guesses - what I urge you to do is talk it over with your doctor. cheers and good luck.

Thanks @joe - I was wondering about the unit values myself. I started on UB40 remember that?!), then U80 and then U100, but I just there are even stronger ones available now.

Okay, so this issue actually started happening on Lantus. I was having the same issue but much more severe. The only difference was that the lantus seemed to stop covering me at the 18h mark. So all day it would be crashing lows, and then I would go to bed and wake up at 400.

I tried eating carbs without dosing for the first 30 minutes and it seems similar to before. within 30 minutes of eating maybe 15 fries I hit 267. I don’t think its my pancreas bouncing back, although I hoped at first.

My issue with all of this is that I am scared to do over a half unit for anything at this point. I think I am just going to make the jump over to a pump.

This way the corrections I make are way more precise. I recently moved from Florida to Colorado. I think that is what is causing this but I can’t decide if it is the altitude or seasonal. I have seen many people on here saying that seasonal changes mess with their basal.

Thank you for taking the time to respond.

I agree that Tresiba is much stronger. I was on 20u of U100 Lantus before the switch.

I am also on U100 Novolog. I am sure I am not walking more or anything like that. I was at first maybe 4 mo ago before this started, but now I am not leaving the house out of fear of crazy drops in public. plus covid.

I did a 16 hour basal test with the Dexcom G6, basically no food until 8p after the previous night.
I am still trying to figure out my carb ratio. It seems that foods are more finicky now, and I am honestly splitting up my doses because I am scared to do over a unit at a time.

I know that isn’t great, but everyone in my household is tired of my anxiety over this and I cant just keep having 2 down arrows every time I am eating lol.

Also, good to note that I have been on a CGM this whole time and have about a month of raw data I have been begging my endo to look over LOL.

@joe @wadawabbit other thing to note is that the insulin gets into my system so quick!
Its working within 10 minutes and out of my system in about 45-1 hour.

I’ve heard some work super fast but didn’t recall the details. Yikes!
There is an inhaled version of Glucagon now - it sounds like it’s easier to administer since you don’t have to mix compenents. Hopefully you’ll get things worked out so it won’t be such a worry.

Hi Ashlyn @ashlyn901, I can mostly understand where you are at, and can relate to your insulin sensitivity.

It is well known that YOUR body needs the amount of insulin it needs - that is, each of us has her/his own body and only a few of us perform just as “The Book” says we should. My own history over the past seven decades will show that at times, MY body needed 100+ units per day, and currently my daily total, while eating 200+++ carbs a day is about 22 units.

I agree with what @Joe, a guy who has helped me learn much about diabetes, said when comparing Lantus and Tresiba. I’ve used Lantus but not Tresiba, but in my research a while back, I may have “discovered” reasons why significantly few units may be needed.

Insulin sensitivity: Your 90 mg/dl per unit is close to my Correction Factor [ISF]. Keep in mind, that your ISF can vary during different periods of the day. From 5:30 AM until about noontime, I use an ISF of 70:1, the rest of the day, my ISF is 85:1 - not much different than your 90:1. My thought for you is to accept what insulin your body needs, and the rate at which YOU need insulin and don’t let Test Book Averages scare you away; and, eat more carbohydrates - they will help you live a long, and healthy life. Don’t over eat, but eat healthy.

My question is how do you get over the fear of rapidly dropping sugars? It seems like now any overcorrection I do, I drop so fast. I end up watching my cgm like a hawk after every meal carbs or not.

@ashlyn901, over the years, I’ve tried to train myself to avoid the sudden drop. I do still experience some although not too often.
My "trick " is by not overcurrecting. Easy said , but more difficult to put into practice. I subtract my Target from BGL, divide by my ISF , and then calculate a percentage of the result based on my activity and other factors.
I use Control IQ on my pump which will only deliver 60% of the calculated correction as a bolus. By keeping my ISF high, the calculated correction is relatively small. I much prefer to make two small corrections, spaced apart, than a big correction that will overcorrect.

It is a lot of trial and error.

1 Like

Yeah i think it’s time to get a pump.

That makes me feel better, i’ve been correcting in half unit increments and waiting it out.

Thank you for taking the time to respond


1 Like

Corruption😊? Foiled by auto-correct I gather? Not making fun of you - I can’t tell you how many times it’s gotten creative on me. I’ve had to replace “hairy” with “healthy” many times - a few hours later.
Wishing you well my friend.

I have lived in Denver for 8 years after living at sea level my entire life. I have had diabetes for 57 years. I take Tresiba and Fiasp (Novolog doesn’t work for is very inconsistent). I weigh 132and take 8 Tresiba daily and fron 5 o 7 or8 u of Fiasp depending on meals and exercise. I correct with half units because I am so sensitive to insulin. I have to adjust the Tresiba seasonally by about 1 unit more in winter. My Fiasp requirements are different depending on time of day. Overnight, one unit will drop me more than 100 at times, so I am very careful with correction at say 2:00AM.
Late morning correction for me is about 1 to 50. I use half units all the time both in dosing and corrections.
I hate lows, who doesn’t? So I set my G6 warning beeper to sound at 85 which gives me time to treat without going low, even when exercising.
I will say that living at altitude is different and I have not been able to keep blood sugars as steady as I could at sea level. When I go up to the mountains 8,600 ft say, I require more basal after 48 hours there. Denver is only 5280.
I hope this all makes sense and helps a bit. And I hope you love being in Colorado as much as I do.


My daughter’s correction factor was 1:100 for years (though she’s at 1:50 at the moment) and we were using injections. Do you have the half-unit syringes? Not everyone is familiar with them — I once had to tell the mail-order pharmacy person that yes, they DO exist, because I was looking at a box of the ones they’d sent me last time as we spoke — but they’re really useful if you need those half-unit corrections.