BS dropping rapidly at tea time then a rebound

[sololite]

Hi all,

I am Type 3 since February and treated as a Type 1.

I've been keeping a close eye on things since I've managed to regain most of my pre op weight and noticed a trend in the evening I'm trying to address.

I am going very low straight after my evening meal at 6.30pm and then rebounding to stay high during the night.

Last night's profile is representative of the phenomenon.

At teatime I'm at 14mmol and take 6 units of Novorapid before eating fish/veg/small potatoes/cheese.

Within an hour i see my BS falling sharply and down to 5mmol I eat half an apple but still it's falling so half an hour later eat the other half.

It bottoms out around 3.8mmol and then at 8pm it starts a steady rise up to 10 mmol

10pm-midnight a rise up to 15mmol

Midnight-3am I'm at 15mmol before a gentle slide down.

6am I'm back to 10mmol my usual start to the day.


For background:

I take 4 Creon with each meal and have a hunch that this has shifted the release of sugar into my blood stream outside of the usual window that my insulin is acting.

My Levemir basal is set at 16 units at 7am and 16 units at 10pm. This was set by my diabetes team. I would like to try a basal test but want to understand this tea time low first in case I go too low during the test.

I'd appreciate any advice on this please as I've been too low 4 times in the last 2 weeks where I grind to a halt and have to eat sweets and wait for the recovery and inevitable rebound.

Regards,

Chris

 

[Inka]

I’m Type 1 not 3c, which I understand has its own extra difficulties, but in your situation I’d experiment with moving the time of my bolus injection and/or splitting it into two injections. How long before your meal do you inject?

 

[sololite]

Thanks Inka. I usually inject 15 mins before or at the time of meal. It seems to make no difference. I wonder if I should be injecting some time after the meal. I didn't know you could split the novorapid. Something else to research. Trying to stay positive. I will get there I'm sure but it does feel like nailing jelly to the wall 🙂

 

[Pumper_Sue]

Thanks Inka. I usually inject 15 mins before or at the time of meal. It seems to make no difference. I wonder if I should be injecting some time after the meal. I didn't know you could split the novorapid. Something else to research. Trying to stay positive. I will get there I'm sure but it does feel like nailing jelly to the wall 🙂

Perhaps lower the amount of insulin for your evening meal. Normally if you go low within 2 hours of your bolus then it's a bolus problem.
If you are dropping at a rate of knots then you need some quick acting carbs like jelly babies to bring you up quicker.
Learning to carb count and adjusting the amount of insulin for carbs eaten would more than likely solve the problem.

Doing a basal test is fine. If you go hypo then just have some JB's and call off the test.
The fact you are 14 before your meal would suggest a basal test is needed then move on to sorting out your meal time needs.

 

[Inka]

Thanks Inka. I usually inject 15 mins before or at the time of meal. It seems to make no difference. I wonder if I should be injecting some time after the meal. I didn't know you could split the novorapid. Something else to research. Trying to stay positive. I will get there I'm sure but it does feel like nailing jelly to the wall 🙂

Well, if you’re dropping low I wouldn’t inject that far in advance. Depending on the time of day, you might find you need to inject just before your meal, during or after. Sadly, the only way to find out is by experimentation. If it were me, I’d try after and see what happens.

 

[SimonP]

If you're 14mmol/l before you eat, I would be trying to sort that out first so perhaps inject 2U an hour or more before you eat - i.e. don't try to deal with the high and the carbs in the single dose, as it sounds like you're probably not eating all that many carbs so if you get either part of the dose wrong you end up going low - if you could let us know roughly how many carbs and what your ratio is that would be useful.

The running high later on may be partly hypo rebound liver response, partly over-treatment (not pointing fingers, I always get it wrong), from the description there's protein and fat so you may also be getting a BG rise from those (if not many carbs in the meal) as well as a delay due to the time it takes to digest them, and you may also be more insulin resistant in the evening - I am, so I tend to need to give myself more insulin a couple of hours after eating no matter what.

It also sounds like your basal is also too high if you're dropping that much overnight - which for the time being you're probably happy about, but once you can get stable blood sugar at bed time this will cause problems (though in the short term you can deal with this with a bedtime snack)

 

[sololite]

Perhaps lower the amount of insulin for your evening meal. Normally if you go low within 2 hours of your bolus then it's a bolus problem.
If you are dropping at a rate of knots then you need some quick acting carbs like jelly babies to bring you up quicker.
Learning to carb count and adjusting the amount of insulin for carbs eaten would more than likely solve the problem.

Doing a basal test is fine. If you go hypo then just have some JB's and call off the test.
The fact you are 14 before your meal would suggest a basal test is needed then move on to sorting out your meal time needs.

Thanks Sue. Great advice

 

[sololite]

Well, if you’re dropping low I wouldn’t inject that far in advance. Depending on the time of day, you might find you need to inject just before your meal, during or after. Sadly, the only way to find out is by experimentation. If it were me, I’d try after and see what happens.

Thanks Inka. It only seems a problem with the evening meal. I will experiment

 

[sololite]

If you're 14mmol/l before you eat, I would be trying to sort that out first so perhaps inject 2U an hour or more before you eat - i.e. don't try to deal with the high and the carbs in the single dose, as it sounds like you're probably not eating all that many carbs so if you get either part of the dose wrong you end up going low - if you could let us know roughly how many carbs and what your ratio is that would be useful.

The running high later on may be partly hypo rebound liver response, partly over-treatment (not pointing fingers, I always get it wrong), from the description there's protein and fat so you may also be getting a BG rise from those (if not many carbs in the meal) as well as a delay due to the time it takes to digest them, and you may also be more insulin resistant in the evening - I am, so I tend to need to give myself more insulin a couple of hours after eating no matter what.

It also sounds like your basal is also too high if you're dropping that much overnight - which for the time being you're probably happy about, but once you can get stable blood sugar at bed time this will cause problems (though in the short term you can deal with this with a bedtime snack)

Thanks Simon. I am going to bounce this off my diabetes nurse this week. I've been trying to follow DAFNE for last couple of years. Very interested to hear you say the basal is too high. Each time I've spoken to my hospital the advice is mostly to add more basal. Did you work out what is best for you or did you follow advice? I see you are a cyclist too. Cycling Is great for my general control but I wonder if long rides are affecting my insulin sensitivity. Regards, Chris

 

[rebrascora]

Could exercise be a factor in this equation too, since I believe you are a sports enthusiast? Wondering if you exercise before your evening meal, if that is causing the NR to have more of an impact when you inject it. I would agree with @Inka that you need to experiment with when you take your bolus and probably split it, particularly if your levels are consistently high/above range before your meal or as suggested by @SimonP tackle this issue in advance of your evening meal, but be cautious if you are exercising during this premeal period because exercise will make you much more sensitive to insulin on board. It is also worth noting that intensive exercise which stresses your body can push your levels up during and immediately afterwards but then reduce them later, whereas more gentle exercise will drop levels during and afterwards but more gradually, so the type of exercise as well as when you do it might be a factor here. Ie. If you have had an intensive workout before tea, this may be giving you a false high and then the insulin is dropping you as well as the exercise, making the drop more dramatic and significant, so might be worth considering what type of exercise you do if exercise may be impacting things here.

My gut feeling is that there is probably a basal insulin problem that needs resolving too so your instinct about basal testing is a good one. It is rare for people to need even doses of Levemir evenly spaced. By comparison I need a lot more in the morning (currently 22 units of Levemir but just 3 at night) This is an extreme of the spectrum but at the other extreme some people need less in the morning and more at night.

I would also query what you are basing your decisions to eat extra carbs on. If you are going solely off Libre then this may be causing you to eat extra carbs when you don't need to as Libre often exaggerates the rate of drop of BG because it extrapolates the previous readings to predict what your current reading will be in 15 mins time in order to overcome the lag between interstitial fluid which it reads and BG. This is fine when levels are not changing too much but when you have insulin (and perhaps the effects of exercise) bringing you down fast and then food starting to digest and release glucose to bring you up, it shows a false picture in the same way that treating a hypo does and you cannot rely on Libre to show you the true level in these situations, so it may be best to do a finger prick before eating more carbs when Libre is showing you dropping like that and you are tempted to eat more. An apple is about 15g-20 carbs which would raise your levels by 4.5-6mmols higher than you would like, so that apple eaten perhaps unnecessarily, could be what is throwing your levels so badly out and then your evening basal may well be too high but at least bringing you back down to a better level through the night whilst you sleep. If you didn't go so high after your meal, you would manage with less evening Levemir and have better time in range. Sometimes we are tempted to respond to Libre because it gives us so much data but that data isn't always correct and doesn't always need us to respond to it.

I think there are potentially lots of issues here and without knowing all the circumstances it is difficult to pin point any one issue. Did your Libre show you going into the red on the graph (not the actual log numbers) as this would be a good indication that Libre may be leading you astray. The graph readjusts for this algorithm shortfall where it over predicts drops and indeed peaks, and the graph will usually show a more true picture later, so if the daily graph does not show you hitting the red or even getting close, then eating your apple after the meal may not have been necessary. I tend to use one JB in these circumstances if I get to 4.2 (where my low alarm is set) with a vertical downward arrow as I JB (5g carbs) is usually enough to stop the drop and the meal I am eating is then enough to take me back up. The 5g carbs doesn't throw me too high after the meal like 15-20g of carbs from an apple would although I appreciate the apple is more nutritious.The JB also gives me a slightly quicker response to my fast dropping levels than the fructose bound up with fibre which will slow it down slightly, in an apple.

Those are my thoughts for what they are worth. 🙄

 

[counsellorneil]

I agree with the thought above about doing a basal test. Although I'm type 1, not 3, so there will be some differences. You may know how to do such a test. I didn't until recently and wish I'd known about this type of test years ago. I did it last week on a morning when I had a decent glucose reading when I woke up. Took my basal insulin as usual, then didn't eat anything, and only had water to drink until lunchtime. It was interesting for me to see a slight glucose rise during the morning. Perhaps not significant, but something I'll be discussing with my DSN next week when I see them, as think my basal rate needs slightly adjusting. You may be surprised by your results. I've been told getting the correct basal rates set is quite crucial to adjusting any bolus rates.

 

[SimonP]

Thanks Simon. I am going to bounce this off my diabetes nurse this week. I've been trying to follow DAFNE for last couple of years. Very interested to hear you say the basal is too high. Each time I've spoken to my hospital the advice is mostly to add more basal. Did you work out what is best for you or did you follow advice? I see you are a cyclist too. Cycling Is great for my general control but I wonder if long rides are affecting my insulin sensitivity. Regards, Chris

I've been doing this a long time, so I do it all myself (though I do listen to people, with a pinch of salt), perhaps there are better resources these days... I have had a good run of consultants over the years, but everyone is different so I think it's very hard for them to be able to offer actionable advice with the level of detail I want. I also note that none of them were experts in endurance exercise, which is probably not surprising, but they were keen to point me towards online resources and let me get on with it.

I second the vote for doing a basal test (not that I've ever done one properly) and also the note re exercise affecting overnight blood sugars - there are some threads lurking about this if you search for my name, and probably more before I joined the forum. Some of this thread might also be interesting to you as a cyclist: https://www.diabetes.co.uk/forum/threads/endurance-sport-to-bolus-or-not-to-bolus.194464/

 

[sololite]

Could exercise be a factor in this equation too, since I believe you are a sports enthusiast? Wondering if you exercise before your evening meal, if that is causing the NR to have more of an impact when you inject it. I would agree with @Inka that you need to experiment with when you take your bolus and probably split it, particularly if your levels are consistently high/above range before your meal or as suggested by @SimonP tackle this issue in advance of your evening meal, but be cautious if you are exercising during this premeal period because exercise will make you much more sensitive to insulin on board. It is also worth noting that intensive exercise which stresses your body can push your levels up during and immediately afterwards but then reduce them later, whereas more gentle exercise will drop levels during and afterwards but more gradually, so the type of exercise as well as when you do it might be a factor here. Ie. If you have had an intensive workout before tea, this may be giving you a false high and then the insulin is dropping you as well as the exercise, making the drop more dramatic and significant, so might be worth considering what type of exercise you do if exercise may be impacting things here.

My gut feeling is that there is probably a basal insulin problem that needs resolving too so your instinct about basal testing is a good one. It is rare for people to need even doses of Levemir evenly spaced. By comparison I need a lot more in the morning (currently 22 units of Levemir but just 3 at night) This is an extreme of the spectrum but at the other extreme some people need less in the morning and more at night.

I would also query what you are basing your decisions to eat extra carbs on. If you are going solely off Libre then this may be causing you to eat extra carbs when you don't need to as Libre often exaggerates the rate of drop of BG because it extrapolates the previous readings to predict what your current reading will be in 15 mins time in order to overcome the lag between interstitial fluid which it reads and BG. This is fine when levels are not changing too much but when you have insulin (and perhaps the effects of exercise) bringing you down fast and then food starting to digest and release glucose to bring you up, it shows a false picture in the same way that treating a hypo does and you cannot rely on Libre to show you the true level in these situations, so it may be best to do a finger prick before eating more carbs when Libre is showing you dropping like that and you are tempted to eat more. An apple is about 15g-20 carbs which would raise your levels by 4.5-6mmols higher than you would like, so that apple eaten perhaps unnecessarily, could be what is throwing your levels so badly out and then your evening basal may well be too high but at least bringing you back down to a better level through the night whilst you sleep. If you didn't go so high after your meal, you would manage with less evening Levemir and have better time in range. Sometimes we are tempted to respond to Libre because it gives us so much data but that data isn't always correct and doesn't always need us to respond to it.

I think there are potentially lots of issues here and without knowing all the circumstances it is difficult to pin point any one issue. Did your Libre show you going into the red on the graph (not the actual log numbers) as this would be a good indication that Libre may be leading you astray. The graph readjusts for this algorithm shortfall where it over predicts drops and indeed peaks, and the graph will usually show a more true picture later, so if the daily graph does not show you hitting the red or even getting close, then eating your apple after the meal may not have been necessary. I tend to use one JB in these circumstances if I get to 4.2 (where my low alarm is set) with a vertical downward arrow as I JB (5g carbs) is usually enough to stop the drop and the meal I am eating is then enough to take me back up. The 5g carbs doesn't throw me too high after the meal like 15-20g of carbs from an apple would although I appreciate the apple is more nutritious.The JB also gives me a slightly quicker response to my fast dropping levels than the fructose bound up with fibre which will slow it down slightly, in an apple.

Those are my thoughts for what they are worth. 🙄

Thanks Barbara for such a detailed response. I really appreciate you supporting me. I experimented yesterday by keeping everything under control yesterday with a cycle after breakfast and a walk before tea. I reduced my novorapid at tea time back to my pre op 1 unit:10g carb and the post meal fall in BS didn't happen. Fantastic but my BS slowly climbed in the middle of the night up to 20mmol and this morning am on 15. I don't finger prick but rely on libre for everything. I really don't want to go back to that. Do you have any thoughts on the big rise in the night? Regards, Chris

 

[sololite]

I agree with the thought above about doing a basal test. Although I'm type 1, not 3, so there will be some differences. You may know how to do such a test. I didn't until recently and wish I'd known about this type of test years ago. I did it last week on a morning when I had a decent glucose reading when I woke up. Took my basal insulin as usual, then didn't eat anything, and only had water to drink until lunchtime. It was interesting for me to see a slight glucose rise during the morning. Perhaps not significant, but something I'll be discussing with my DSN next week when I see them, as think my basal rate needs slightly adjusting. You may be surprised by your results. I've been told getting the correct basal rates set is quite crucial to adjusting any bolus rates.

Thank you @counsellorneil I am going to do the basal test

 

[sololite]

I've been doing this a long time, so I do it all myself (though I do listen to people, with a pinch of salt), perhaps there are better resources these days... I have had a good run of consultants over the years, but everyone is different so I think it's very hard for them to be able to offer actionable advice with the level of detail I want. I also note that none of them were experts in endurance exercise, which is probably not surprising, but they were keen to point me towards online resources and let me get on with it.

I second the vote for doing a basal test (not that I've ever done one properly) and also the note re exercise affecting overnight blood sugars - there are some threads lurking about this if you search for my name, and probably more before I joined the forum. Some of this thread might also be interesting to you as a cyclist: https://www.diabetes.co.uk/forum/threads/endurance-sport-to-bolus-or-not-to-bolus.194464/

Thanks Simon. I never imagined managing diabetes would be so complicated. I just skimmed your thread. There is a lot there for me to digest and try and draw parallels to. I am nowhere near your levels but I think I can learn from it. At the moment I just about manage a hilly 35 miles (we are in the purbecks) but fade on the last 10 even though my BS is good and I've had good breakfast and coffee/flapjack at halfway. Regards, Chris

 

[SimonP]

Thanks Simon. I never imagined managing diabetes would be so complicated. I just skimmed your thread. There is a lot there for me to digest and try and draw parallels to. I am nowhere near your levels but I think I can learn from it. At the moment I just about manage a hilly 35 miles (we are in the purbecks) but fade on the last 10 even though my BS is good and I've had good breakfast and coffee/flapjack at halfway. Regards, Chris

Don't worry I remember those days, it gets easier the more you do (or as they say it's equally hard but you go faster! 🙂)

Thanks Barbara for such a detailed response. I really appreciate you supporting me. I experimented yesterday by keeping everything under control yesterday with a cycle after breakfast and a walk before tea. I reduced my novorapid at tea time back to my pre op 1 unit:10g carb and the post meal fall in BS didn't happen. Fantastic but my BS slowly climbed in the middle of the night up to 20mmol and this morning am on 15. I don't finger prick but rely on libre for everything. I really don't want to go back to that. Do you have any thoughts on the big rise in the night? Regards, Chris

Could you give us some more detail about your tea time meal, etc., what time, what did you eat, how many carbs and how much insulin did you take?

As you still drop overnight, I'd be tempted to leave the basal alone (do a basal test anyway at some point), and I wonder if you either have low insulin sensitivity at supper time or are eating something that is slowly absorbed or a bit of both.

I have to dose more than my usual rate for my supper (though oddly I have very high sensitivity in the early afternoon, it's all fun and games 😉), and to avoid taking large amounts of insulin when I eat supper I split my dose so that I never have too much onboard until I can see that I'm getting a trend after I've eaten. Before I started doing this I was also suffering from going low immediately after eating supper, then needing to eat something to fix that, take a correction dose and still then having my BG rise in the late evening and into the night (though mine would stay high as my basal was ok).

Once I split dose and removed the lows, I could see that I actually did need to take more insulin that I was expecting for my evening meal and over a longer duration.

 

[trophywench]

Hells bells - no way could I trust the Libre to tell me the truth in numbers, only in arrow directions. Plus, the bolus wizard for my pump is actually programed into the meter/pump remote control and the Libre doesn't communicate with my pump whatsoever, hence if I really need to know what's going on in my bloodstream, BG meter it has to be. Snacks between meals, shall I have dessert, wonder if I can afford to have any more Quality Street out of this tin being waved - well OK, quick glance at Libre scan.

It differs between different sensors as to how accurate or not, it happens to decide to be, but as I also found this with Libre 1 (though admittedly more so with the 1) so I've never wholly relied on it, nowt has changed. I had intended to enquire if i could change to a Dexcom or summat else to see if more reliable, but as the doc said she knew nowt about Libre anyway so I'd have to talk to a DSN who wasn't in that day 'not me' - I couldn't discuss it. Very annoying! Not at all what I was expecting all in all.

 

[Wendal]

Hi Sololite,
Sorry to hear about your up and down BG readings and as others have said 3c can be more volatile due largely effect of glucagon as well as the insulin,plus your Pancreas may still be producing one or both depending on your situation.
There have been some great responses and especially Barbara point about Libre readings which can be misleading when levels are rapidly changing up and down and of course often govern our response.
I am only 3 weeks in so very new to this and nowhere near experienced as many on here but if there is one experience I have found beneficial it is to try and sort/ deal with one issue/ concern at a time rather than try and deal with multiple events.
Once you get one thing “ sorted” ( but appreciate it may take a while) it makes it easier to make other adjustments in terms of better understanding of how individuals respond.
So my first priority was to get my high levels down ( average Week 1 was 13.5 week 2 10.5 and week 3 now 8.6.
Then try and sort out overnight routine ( still keeping a bit high to avoid going to low but recognise I need to start lower once my insulin is fine tuned.
Then try and get my day time sorted and then hopefully put it together by increasing time in range to my target levels.
Then to try and bring my average down once I am happy with my TIR.
Am not making any adjustments to my insulin levels myself but relying on DSN advice only but making small adjustments re very moderate exercise and again sticking to regular diet and only responding to lows ( usually have a regular mid morning low but I have my alarm set high at 5.5 just to forewarn me of I need to monitor closely.
If it settles fine or if it keeps dropping I will take some action depending on level and direction but trying not to overreact like I did the first time it dropped low.
As I said others will have a lot more experience and you are exercising much more than me but to me making one change at a time then trying to assess that variable works best for me rather than trying to deal with multi factorial issues all at once.
So if I was in your situation I would look to getting your pre evening meal BG level addressed first of all and try and ascertain if it is an exercise/ diet or insulin therapy related issue.
Hopefully once you have better understood why that is so high then maybe get that more in the range and you can see how your body responds and maybe if that is lower then perhaps the response to your meal is less volatile.
So do try different things but keep the other variables the same if that makes sense.
VBW

 

[helli]

I don't finger prick but rely on libre for everything. I really don't want to go back to that.

Do you have a problem with occasional finger pricking?
As has been mentioned many times, Libre has known limitations which means there are times when you should finger prick.
For example, it is designed to be most accurate at "normal levels", between about 4 and 8. Outside of this range, it can be very inaccurate. If you are seeing numbers frequently in the teens, Libre is not much use. I would certainly never use a number that high from Libre to make a correction dose.

Unless you have a major issue with the occasional finger prick, I strongly recommend checking your Libre more often.

 

[sololite]

Hi Helli. I know you are right. My response was shooting from the hip. So much advice recently seems to challenge my diabetes teams guidance and to hear that even libre might be misleading was depressing. I will do a spot check tonight if I wake up and am high which I am anticipating