How do you know when you need to decrease insulin?

So for the last month I hqve been having lows at night. I don’t feel them and I certainly feel 72 when I wake up is too low. I go to bed around 140 so I don’t get too low but doesn’t help. I take 12u of Lantus in the morning and 8u at night. I take Novolog early in the evening so it doesn’t drop my BS too much at night. I’m eating better and moat of my carbs are at night. What do you guys think?

Hi Quigley! It’s a little hard to advise without more info but I’d say from experience that it just is difficult to get that overnight thing dialed in with Lantus. Even splitting doses, it’s a fairly blunt instrument relative to how your metabolism actually behaves. But since that’s what you’re using, one thing that strikes me: [quote=“Quigley83, post:1, topic:55278”]
most of my carbs are at night
Everyone is different of course, but I find that restricting my carb eating to the middle of the day gives me much more opportunity to monitor and take whatever action I need to even things out before bedtime. A stubborn post-prandial high or an accidental over-bolus low is much easier to deal with at 3pm than at 3am. Your metabolism has its own routines during sleep cycles and you’re not there, so to speak, to react to them. Short of switching to a pump, which gives you the kind of fine-tuning options you really need for this sort of thing (and I realize there can be lots of reasons why a pump just isn’t an option for some), I think this may just be a case where, if you really want to get a handle on it, you have to adjust your behavior to your treatment and not the other way around.

I do agree with @DrBB that carbs at night can make things more difficult. But you may find that you need to work on your basal anyway. A good way of doing this is basal testing. The ideal goal of basal testing is to establish your basal dose to keep you “flat” overnight, ideally rising or dropping less than 10 mg/dl on average. If you are routinely dropping an average of 70 mg/dl overnight then you might consider adjusting your basal. You can adjust the dosing and timing of your Lantus, starting with your nighttime dose. Lantus reaches a peak at 4-5 hours, so you need to work back. If you have a CGM it is much easier to see when you have lows and how bad they area. With basal adjustment it is best to make a small change (like 5%) and then observe things for a few days to see how you do on average.


Okay so last night when I went to bed it was 164. I have to keep it higher before bed because it drops. When I woke up this AM it was 95. Perfect. But I can’t be below 140 before I go to bed or else I drop too low. I take Novolog around 5pm. Eat and then take Lantus around 7pm. I’ve heard Lantus May not work 24 hours so that’s why I split my dose. Would worth to venture taking Lantus once a day in the morning? I’m a complete rookie and can’t figure out what to do.

And although I eventually want a cgm and pump…I haven’t been on this rollercoaster long and ant to figure out MDI for a year or so and mentally prepare myself with a pump.

My point is that consistently dropping 70 mg/dl overnight suggests that your basal levels overnight are too high, not that you have to carb load before going to sleep. It is best to be flat overnight hen you are asleep and not as able to manage the dynamics of changing blood sugars.

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The only problem I have with carbs in the mid day is work. I try to be consistent so it doesn’t affect it. And my body gets tired at 2 or 3 pm so don’t like to have many carbs in the afternoon.

Just want to echo that basal testing appears to be in order. IMO, being over 100 any time of the day or night is higher than I like my daughter to be. I correct anything over 100 before bedtime. And many PWD who have tight control don’t consider BGs in the 70s to be low.

It’s difficult to achieve this kind of fine-tuning without a CGM. And for my daughter, a pump.

As far as figuring out what to do, I highly recommend reading Gary Scheiner’s Think Like a Pancreas. IMO this should be “required” reading for anyone with D, especially Type 1. So many of your questions regarding how to fine-tune your insulin dosing will be answered there. Good luck and keep us posted!

Many folks who don’t pump and who therefore cannot utilize variable basal rates throughout the day and night have had great success with switching to Tresiba as their basal insulin. If my daughter ever decides to take a pump break, I have a rx for Tresiba “on file” at our pharmacy.


140 is high. Not life-threateningly, catastrophically high, but high all the same. If you’re having to go to bed at 140 just to wake up in a reasonable range, your basal is not dialed in correctly for your individual physiology. Compensating by carb-loading is fraught with risk and isn’t the answer; that’s like driving at 100MPH because you’re already late. Getting the basal right is the answer.

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I’m having trouble figuring out my basal too (well, I’m having trouble with all of it, really) and I’m pretty sure its because my doctor has me on the sliding scale method for bolus. Its so stupid. I’m either too high or too low (mostly too high) all the time and never where I want to be. The frustration is becoming overwhelming.

Sliding scale insulin dosing is a reactive tactic. You constantly respond to high blood sugar. It’s not a good system.

You need to adjust your basal rates before attempting to figure out bolus and correction ratios.

@Terry4 Thank you so much for that bit of info (figuring out basal before bolus)!!! It makes sense to me now! My doc has me emailing him my fasting blood sugars every 4 days. Until my 4 day average is under 140 he’s increasing the dose by two units. I have just finished 4 days of 16 units and I think it’s the magic number. My average is 132. I’d like it to be lower so I might increase it another unit or two. We’ll see what the doc says today. My fasting bs used to run in the low 200’s!! My doc did mention that he was going to approach my basal rate cautiously as not to cause too many lows during the day (LADA with a sputtering, unreliable pancreas). Sadly, I think my beta cells have given up the fight.

Hi Becca! I started to take 14u in the AM and nothing at night. Go to bed at about 100 and just woke up with 90. I was doing it all wrong for months but it’s a process right? Changes everyday.

Basal testing

this may help with bolus

A workbook (the certificate ran out but the site is safe)


Jack. This information has been invaluable. Thank you for taking the time to respond. Basal testing…here we gooooo. =)

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