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Splitting basal

lizdeluz

Well-Known Member
Messages
1,306
Type of diabetes
Type 1
Treatment type
Insulin
If you are on MDI, do you split your daily basal insulin dose? If you do, I'd be grateful if you could explain the benefits. I take 20u Lantus Glargine before breakfast and am considering whether to change to injecting two smaller doses per day.
My current estimated hba1c is 6.5%. I should maybe try to improve on this.
 
A lot of us on MDI split our basal doses. It generally improves control as almost all the "once daily" basal insulins available today don't actually last 24hrs. This means that for a lot of us, our BG tends to rise towards the end of the 24 hour period resulting in the need for repeated bolus corrections or raised HbA1c's...

With Levemir, I work an even split 12 hours apart. Some find that they need more during the night so would adjust the dose to suit that. The bonus of splitting my basal is ease of adjustment for increased/decreased carb intake. So on days where I've increased my carb intake (raised total daily insulin dose), I can increase my evening basal dose to compensate for that extra carbohydrates. Likewise, if I've not eaten as much, I can reduce it. I know that my basal needs are 60% of my TDD, so I can adjust my doses every 12 hours if I ever need to.

I'd seek advice from your DSN if you aren't overly confident with splitting your dose though. It also never hurts to get a little bit of professional input anyway.

Are you finding that your BG is gradually increasing towards the end of the 24 hour period? You may find that simply taking your insulin in the evening instead of at breakfast will help too.
 
I was, a long time ago, on only Lantus at night but that was changed to a split morning/night dose. I have no idea when this happened but could have been more than 10 years. I did read sometime over the last few years that that whilst Lantus was supposed to last 24 hours they discovered that many people were better off with a split dose. The DAFNE standard is 10 units in the morning and 14 at night then adjust to get the reguired BGL.
 
If your BG in the morning is within range and your HbA1c is good then i personally see no reason for the need to split your basal. By all means spesk to your Diabetes team.

Regards

Martin
 
Thank you very much for your replies. I'm sorry I've been slow to write back. I've been thinking hard about the points you make.
@GrantGam1337 I'm certainly not confident about managing my injections, I just do the best I can and feel that it could be better and am never sure how to make it better. Some forum members may have a suspicion that I have already asked about splitting basal months ago and may wonder why I've done nothing! I need another push towards some basic reading about how long -acting insulin works, and any problems associated with Lantus that you may know of. I'd be very grateful for any links: I'll do the reading, and report back when I make the split.
@Blackers183, thank you for the Dafne info, the 10/14 split sounds like a good starting-point for me.
Martin, yes, I'm possibly worrying unnecessarily but I'm just trying to stave off the dreaded complications! I'm not as happy with my bs as my DSN and consultant are.
This morning, I happened to wake at 04:15, did a test and my BG was 4.9. No snack, no insulin. I went back to sleep and my next test was at 08:20, an hour later than my usual fasting test. BG was 8.0. I injected 3u NovoRapid for my 8g carb breakfast, and 20u Lantus to cover background needs for 24 hours.
I'm in awe of other Type 1s who can see patterns in their bs. For me, it's like looking for a needle in a haystack. Every day totally different. The margin of error is much much better since I started a low carb diet, so that has improved things for me a lot, my general health is much more stable. However I am also a bit of a technophobe, and get irritated when my wonderful Accu-chek meter (which is a godsend and I'm lucky to have it) times out because I think too slowly! :banghead::)
 
Splitting also allows you to adjust for things like exercise and illness without having to effect the rest of the day......

I personally had a significantly different basal need between AM and PM.....
 
Lantus can be erratic apparently - I've never taken it but I remember a few on here were suffering random night time hypos and swapped to Levemir which helped, splitting levemir is generally more acceptable/common (?) this will give you more to search and read up on!

If you are suffering night time hypos (with or with out knowing about them) then may be these are causing your needle in a haystack affect?
 
@GrantGam1337 I'm certainly not confident about managing my injections, I just do the best I can and feel that it could be better and am never sure how to make it better. Some forum members may have a suspicion that I have already asked about splitting basal months ago and may wonder why I've done nothing! I need another push towards some basic reading about how long -acting insulin works, and any problems associated with Lantus that you may know of. I'd be very grateful for any links: I'll do the reading, and report back when I make the split.
That's quite alright though, it's a decision you're quite right in not taking too lightly. Even the smallest of errors in adjusting insulin doses can have consequences.

To put it simply, basal insulin allows for the storage of glucose (released by the liver) in the body's cells for fuel. Without basal insulin, all the glucose which is released by the liver would continue to circulate in your blood stream and elevate your BG.

The above is in my own words, but you'll find more detailed explanations in the book: "Think Like A Pancreas". Below is the Kindle version (which is cheaper) but it's also available in a hard copy:

https://www.amazon.co.uk/Think-Like.../ref=tmm_kin_swatch_0?_encoding=UTF8&qid=&sr=

Have you spoken with your Dr or DSN about splitting your basal?

If it were me, I'd work out 80% of my total basal dose and then split that value in half and take it every 12 hours. So for example, if I was taking 28u Lantus - 80% is 22.4u which works out at 11.2u every 12 hours. I'd round that 11.2u down to 11u.

Once you've split your dose then you can gradually increase your insulin amounts if need be. Taking 80% of the original once daily dose is a means to prevent unnecessary hypos and might be less than you actually require, although when changing doses - it's always best to err on the side of caution.

EDIT - to replace mobile link with a desktop friendly version.
 
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I started to split my levemir dose about two weeks ago. I realised through basal testing it was running out the evening and I was compensating with bolus insulin. So far it's worked well steadier bg but it's early days. Worth discussing with dsn and maybe doing some basal testing at different times in day.
 
I realised through basal testing it was running out the evening and I was compensating with bolus insulin

This is spot on, and exactly what I found. @lizdeluz suggest you go over you're test results and notes to see if this pattern is happening to you. As your control is very good I wouldn't change basal unless this was happening. EDIT to say your 'evening' rise would probably be during the night though.

If you want tighter control have you looked a bolus timing?
 
If you want tighter control have you looked a bolus timing?

I saw a cross-reference to a really useful thread on this which seemed to appear by magic, thank you if someone did the cross-referencing. I'm too haphazard about timing I think and it's something I could and should put into the constant equations. I wasn't expecting to have to handle maths when I got my diagnosis.:(
 
I'm going to praise bolus timing too : D It really can be an amazing tool and can have a much bigger affect on BS than you'd imagine.
 
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