Splitting long acting dose

Why do some people split their long acting dose, so for example they'll take 10 units in the morning then 10 at night rather than taking the full amount once daily. What are the pros/cons to doing this?

Hi Dani. People do that because long-acting insulin is supposed to last 24 hours but often doesn't so there is a gap in coverage. By taking it in two doses, the overlap serves to cover the gap.

Also it takes an hour or more to ramp up to full strength, so again the 2 dose overlap covers that gap.

It's my understanding that splitting the long acting dose also allows for treating more resistant BGs that often occur in the morning. So, using your example, the PWD could split the 20 unit daily dose into 11 at night and 9 in the morning. PWD basal needs are not always uniformly distributed throughout the day.

The smaller the dose, the better the absorption, so splitting helps since you may use less insulin. I (like others) don't believe that basal insulins actually last 24 hours, so splitting can help flatten the profile. And I split my doses unevenly like Terry describes in a valiant attempt to get more insulin overnight to reduce my Darn Phenomenon. Bernstein also believes that overnight a basal insulin will have a shorter duration of action due to your body clearing out the insulin at a higher rate. He recommends Levemir and suggests taking half first thing in the morning (that dose lasts 18 hours) and again right before bed (that dose lasts 6 hours).


Lantus is the STRONGEST for the first 6-8 hours.
in some people, it just works better for them to split the dose. everyone is different!

If I took Lantus in the morning I'd be running low all day long, but at night does the trick for me.
Ive heard typ 2's or more insulin resistant people do best on 2 shots a day of it.
I take 12 units once a day at night.

thanks, that was helpful.
I'm taking my Lantus at 1 am right now (set an alarm clock)
b/c I drop low if I take it earlier, and it really does the trick.
(12 units)
I wonder if Dr. B's way would work better for me?

that is so true. I wish they'd stop advertising it as a 24 hour insulin.

It is hard to say, you could try it and see. But Dr. B also says "what works, works."

I have just begun splitting the dose and it's too early to make definitive statements about the result. So far, so good. As for adding another injection to the 6 or 7 I already take . . . trivial. Insignificant.

You also split, because, if you plan on doing exercise lets say during the next day, if you only take one injection a day, you would have to reduce your insulin already in the evening and are therefore high during the night.
so splitting insulin helps delivering more accurate doses closer to your actual needs, instead of just one dose that covers the entire day and night.

And the pump allows you to even more closely ally your basal with your needs!

Curious... couldn't a T1 perform similar empirical experimentation as is done for pumps to determine basal rates to find out one's personal action profile for a long-acting?

I'm thinking, take it before bed on a Friday, then test periodically through the next 18 hours or so keeping careful records of fasting/digesting "mode", watch BG, when it starts to head up while in fasting mode you've found the duration.

Using this datum, various "profiles" for stacking long-acting doses can be put together, and actually a rather complex basal "program" could be constructed.

This might be useful to really get a handle on DP, although the prospect of having to dose at least once in the early morning hours is probably unavoidable.

Lantus' action potentcy is pretty flat until is starts to fall off. There isn't really any "peak".

it's my understanding, we don't adjust our basal insulin on MDI, in terms of exercise, etc...it takes at least three days (some Endos say a week) to show any effects in terms of increasing or decreasing levemir/lantus and both stay around in the body for a very long time.

Also, if I miss or am late with a dose, there is less impact.

I split my basal insulin dose because it peaked about 5 hours after injecting, and would cause low BG.I would also have a rebound in the morning so the split dose corrected some of the lows and the morning dose helped with my DP. This did not correct all of my night time lows so I was placed on a pump and CGMS which gives me a somewhat predictable BG at night...never perfect and always changing but I can sleep without much worry.

Pretty simple, really. Assuming you haven't eaten anything for 3 hours or so when you go to bed, you're in fasting mode. The 12U of Lantus is too much. If you consistently wake up low with the same food pattern in the evening, then start by reducing the Lantus 1U each day until the morning BG is better.

Then, if the lower bedtime dose results in more trouble managing sugars during the day, add back 1U each day in the morning right when you get up, not to exceed a total combined dose of 12U as prescribed by your doctor. See how that works out.

As for the Novorapid, the only truly successful way to deal with that is carb counting, and then calculating based on your IC. You say your using 1:10, which is nice for calculations! Ideally, you'd give yourself a bolus injections every time you eat carbs, not just 3x a day at meals.

Carb counting is pretty easy once you get the hang of it. The hardest thing is estimating -- takes some practice to get a "sense" of how much is in a serving of something, and of course where there is valid nutritional data, use that -- it's dirt simple then.

Dani, I think splitting the dose might help you then. Talk with your endo about this, but it might help to for example give 5 units at night and then 7 units in the morning, so your dose is more accurate to what your body needs…
Hope i could help

Zoe, while most T1's eat far more during daytime hours my endo. insists my two Lantus shots (morning and bedtime) must be the same amount.
I can't make much sense of this. Any ideas?