Type 1 and Insulin Stacking

[ClaireM43]

Hi Guys,
I've had a quick look through previous threads but I can't find an answer to my specific question.
I know that my Novorapid lasts for 4 hours and I'm a bit confused so here is my question.
If I've had my lunch at 1pm and I've done the appropriate Novorapid jabs (ie. 6 units of NR to cover 60 Carb Portions) then that dosage of insulin will have worn off by 5pm. But if I have another big meal at 3.30pm (i.e another 6 units of NR to cover 60 Carb Portions) do I just put in the 6 units of NR for that meal and not worry that the 1pm dosage will still be working?
Any replies will be gratefully received - thanks all!!

 

[ClaireM43]

Hi Benny - yes the units:CP were just an example!! It's the times of the meals and dosages I am unsure about.

 

[trophywench]

Hi Claire

A carb portion consists of 10g carbs - so I think you are most likely only having 6 of em and 1u for each portion ! LOL

Well yes you'd need the full 6units for the second meal and there's no argument with that - but the issue with insulin stacking is that to begin with very soon after jabbing the second 6u, that Novorapid is going to seem 'stronger' than the 6u you had the first time. Of course - it isn't, it's all the same strength but because you already have a decent bit of the first jab left, you get a double whammy until the first lot times out. People often forget this issue, merrily jab away and the effect can be so pronounced sometimes that within half an hour they're well hypo with all the probs that can then arise - need to eat so many jelly babies they then can't eat the meal and spend hours with far too high BG.

Was that a hypothetical occurrence, or does it really happen? If so, in what circumstances?

 

[trophywench]

As Benny said - if it's only very occasionally I'd be likely to avoid some of the carbs in the second meal or preferably, the first one! (or both if you're me cos 60g carb in one go is too much for me most times!)

There are ways of getting around it though eg not eating any spuds with your meat and veg and only injecting for the carb in the first course before commencing eating then having a second jab to cater for the pud before eating that. Much depends on what food it is - we have to be flexible and just get used to doing it when needed.

 

[ClaireM43]

Hi Jenny,
I've just been on the DAFNE course so I'm sitting here trying to make my own notes as a handy little reference guide for myself.
The course has been invaluable but very intensive and a LOT to remember!! I've just got stuck with if I had another big dinner within the four hours before the previous dose of NV runs out. I think your suggestion of reducing/cutting out the carbs in the 2nd meal makes sense. According to DAFNE I think I should be reducing the NR dose for the 2nd meal to reflect the amount of NV that would still be active from the 1st meal. This makes my brain ache so reducing carbs in the 2nd meal would work for me.
Thank you very much!!

 

[ClaireM43]

Sorry that should read as NR not NV.............

 

[TheClockworkDodo]

I sometimes stack a bit, in that I might eat a meal 3.5 hours after the previous one, and my meals are relatively high carb (though my insulin needs are relatively low), so I would inject the full amount I'd expect to need for the second meal. If in any doubt (eg if I had to decide between 2.5 or 3 units) I'd round it down though. I also wouldn't inject any extra/correction dose if my blood sugar were a bit higher than usual, because I'd expect that still to be on the way down from the first injection.

I don't think I'd want a second whole meal only 2.5 hours after a previous one though! If I'm snacking between meals I normally have low carb snacks and don't inject any insulin for them - but if I'm out and having a cake an hour after lunch I will definitely stack my insulin, because I'll definitely need another insulin injection for the cake.

 

[ClaireM43]

No I wouldn't have thought I'd need another meal so quickly after the previous one but I'm just thinking along the lines of what if I did.
What you say makes sense too. I've learnt so much on the DAFNE course but putting it into practice and expecting the improved BG results just isn't happening. I know it will take time to settle down and I'm religiously tracking the BG patterns, counting the carbs and weighing the portions but my BG readings still don't make any sense. I'm double checking to make sure that I've got the dosage right but the readings are still too high. For example - My readings at dinner time (7.20pm) were 7.8 which I was really pleased with and my CP was 54g. I took 5 units of NR + 1 correction unit so 6 NR in total. 4.5 hours later at 11.50pm my BG was 16.4!! I've just done my BI and have corrected with 5 units of NR so will check again in the morning. I'm thinking I need to increase my dinner time ratio from 1:10CP to 1.5:10CP. I think it's the fact that I've had Type1 for 20 years, have always had very high BG levels and now I'm putting into practice my 'new knowledge' and they are still mega-high WHY WHY WHY!!

 

[nonethewiser]

If I've had my lunch at 1pm and I've done the appropriate Novorapid jabs (ie. 6 units of NR to cover 60 Carb Portions) then that dosage of insulin will have worn off by 5pm. But if I have another big meal at 3.30pm (i.e another 6 units of NR to cover 60 Carb Portions) do I just put in the 6 units of NR for that meal and not worry that the 1pm dosage will still be working?

Still need to consider lunch dose still working, in those situations I just reduce the dose, especially if bg is in range and libre is showing downward trend arrow, so instead of 6u going in it would be more like 5u or 4u depending.

Don't worry about carb content, my breakfast lunch dinner work out around 50 60g of carbs, a case of experimenting and learning as with anything in life.

 

[ClaireM43]

Hypo this morning so I'll carry on experimenting with my dosage ratios. I'll see what it is at lunchtime and carry on adjusting until I can see a regular pattern. Basal seems to be fine as I've tested at 3am on two occasions and it's been around 6.5. Thank you all for some very useful replies.

 

[Thebearcametoo]

My understanding was that novorapid peaks 1-2 hours after injecting so whilst there may still be some in your system up to 4 hours later it’s not the majority of the dose if that helps at all.

 

[TheClockworkDodo]

For example - My readings at dinner time (7.20pm) were 7.8 which I was really pleased with and my CP was 54g. I took 5 units of NR + 1 correction unit so 6 NR in total. 4.5 hours later at 11.50pm my BG was 16.4!!

I'd agree with Benny's post about that, but just to add - there are other things which will effect your blood sugar as well as carbs. If you are stressed it will go up; if you are sickening for something it may go up; if you eat something to which you have a mild intolerance it may go up; if the temperature has suddenly changed it may go up (or down!); if you eat something like a pizza which has a lot of carbs and a lot of fat together it may go down at first and then suddenly spike later.

As an example, I have a very mild intolerance to eggs - I can eat them, but they don't really agree with me very much. I hadn't realised that this sort of thing might effect my blood sugar though, so I was struggling to eat them, knowing my diet is lower in protein than it should be, and that they are "good for you". When I got diabetes and started testing my blood sugar I couldn't work out why it went up so much every time I ate eggs. I kept putting my dose for them up and up and up, and in the end I was injecting enough insulin for something like 100g of carbs, if I remember rightly, for something which was completely carb-free - and my blood sugar was still going into the high teens every time I ate them, so I had to stop eating them.

 

[trophywench]

Blimey Juliet - your body clearly has a very marked intolerance to eggs indeed - and were you not T1 you'd never have known how much it struggles with em - makes me realise that such things are an ironic demonstration of D sometimes doing us favours! Plus of course makes it very simple to persuade medics that it isn't all in our heads, so I like that aspect - the patient absolutely often knows more about their body than the doctors do and even if we don't know why - we do know for a fact when it's not 100% 'right'.

Returning to the subject of the thread, thinking about it though I wouldn't eat two large meals in quick succession it's true - what if I had a big fat cake with my cuppa mid afternoon? That can happen, especially when out and about exploring like on holiday - say we were trekking round somewhere touristy eg Bath or York (or Harrogate) and a café presents itself, lovely, I can rest me feet for 10 minutes - and there they are laying in wait to ambush customers - big, fat, fresh cream fruit scones, with the jam oozing down the sides. OK the cream will delay some of the carbs hitting quite as quick but not by much with the carb fest of the entire object!

Or it's freezing cold so sod it I'll have a big fat hot choc instead of a cuppa and while I'm on I may as well have a slice of millionaire's shortcake with it, after all, I've been walking haven't I? May as well be hung for a sheep as lamb!

 

[ClaireM43]

It is so nice to know that I am not alone!! Hypo this morning at 3.5. 30 mins later it's 7.9 so 26 carbs for breakfast and 5 units of NR. (1.5:10 ratio for breakfast). Lunchtime reading at 1pm was 12.9 so I've put in 3.5 units (no lunch and 1:10 ratio at lunchtime). I'm seeing my DSN in a couple of weeks so I'm not too worried but it's just WHY? I am now starving but will wait until 5pm to check BG again. Hey Ho.............

 

[everydayupsanddowns]

It is so nice to know that I am not alone!! Hypo this morning at 3.5. 30 mins later it's 7.9 so 26 carbs for breakfast and 5 units of NR. (1.5:10 ratio for breakfast). Lunchtime reading at 1pm was 12.9 so I've put in 3.5 units (no lunch and 1:10 ratio at lunchtime). I'm seeing my DSN in a couple of weeks so I'm not too worried but it's just WHY? I am now starving but will wait until 5pm to check BG again. Hey Ho.............

I think part of the problem (which diabetes itself creates) is the illusion of simplistic ‘diabetes maths’...

Take x insulin for y carbs. Therefore if you take 2x carbs, you need 2y carbs, right? Well yes. And no. Depending on a pretty large number of other factors.

And sadly I don’t think it’s all that helpful to just say ‘don’t do that’, particularly when as Jenny points out ‘that’ might actually be rather nice!

A couple of thoughts to add to your mix...

Carb counting is GREAT, and works well for me most of the time. But it’s not foolproof. Even when you scrupulously measure things on my experience. It also (for me) doesn’t seem to be completely scalable. Larger single meals seem to need a different ratio. Perhaps 25% or 30% more insulin, but acting over a much longer timeline.

Insulin stacking is also best avoided on the whole. But it can be made to work with a little experimentation.

Most things in my experience seem to revolve around using carb counting as a basis (and continually adjusting doses so that the ‘reliable’ and ‘safe’ meals continue to behave) but also building up an extensive set of personal rules of thumb and exceptions for situations that happen fairly frequently, and just winging it and trying not to stress too much about the rarer circumstances.

 

[ClaireM43]

Thanks Mike - it's great to speak with people who still struggle with long term Type 1. I knew that after the course, I wouldn't just walk away, apply all the factors and suddenly become a well controlled diabetic. I knew that I'd have to be far stricter with counting carbs and weighing (not guessing) portion sizes, follow patterns and make suitable adjustments and that it's very much 'trial and error' but my BG readings are just so random that at the moment I can't see any pattern emerging so I can't alter any ratios. I can honestly say that I have been doing everything by the book so in 2 weeks I'm seeing the DSN so will see what they have to say. Maybe I need a different type of insulin, maybe there is some other underlying problem, who knows?? I've always had high blood sugars (I was diagnosed at 51.2) and my current HbA1c is 88. I keep telling myself that all I can do is carry on with what I'm doing and hopefully in a few weeks a pattern might start emerging. We'll see!!

 

[everydayupsanddowns]

I’ve not formally done DAFNE, so I don’t know if basal testing is part of it, but as someone has suggested, occasionally giving your basal a good looking at through the full 24 hours with a series of fasting tests to miss different meals is well worth the investment and faff. Even if it changes a month later, or you can’t get your basal insulin to quite match it provides a much better bedrock for your meal doses and corrections.

When I was on MDI as soon as I discovered basal testing I realised that if my basal is only slightly out, the rest of my doses start really misbehaving and acting completely illogically.

There’s a write-up here: https://www.diabetes-support.org.uk/info/?page_id=120