How fast is fast-acting meant to be?

[slip]

Basal is suppose to keep you level, you had a slight decrease over the day, but the 3.2 this morning?, I'd do some more basal testing before jumping to any conclusions, Also try and test during the night (a pain I know).

 

[CarbsRok]

Ok I fasted yesterday for 24 hours on Levemir only.
The results:
6am - 12 Levemir, BG 10.8
8am - BG 12.1
11am - BG 10.4
1pm - BG 9.1
4pm - BG 8.8
6pm - 12 Levemir, BG 8.8
9pm - BG 8.2
6am - BG 3.2
So, on the whole it seems to be pretty level. The morning high is not a surprise, the dawn effect always seems to be present, although not this morning when I was low, but again not a surprise after fasting for 24 hours.
Does this tell me that the Levemir as a twin daily dose is right? It seems to.
So back to the question, why, after eating a meal, is it taking four or so hours for my levels to start to drop?

Your levels may be pretty stable in your eyes but are way to high, so obviously a basal problem.
What level are you when you eat a meal as you in theory should be below 8 but 4.5 or 5 would be ideal. It does look as if you are expecting your bolus to do the work of both basal and bolus.

 

[Bluemarine Josephine]

Hello everyone!
I hope that you are all very well today!

What I am about to say may sound completely ridiculous and off topic but, there is a trick with the glycemic index.
I can see you all smiling somewhat ironically now but, just be patient with me.

Following my diabetes nutritionist’s advise, I was all for low glycemic index foods.
I was starting my breakfast, with ridiculously low glycemic load meals which included pumpernickel bread or rye bread or even the Hovis Seeds sensations and olive oil spread to delay the digestion process...

Now here is the tricky bit.
I have breakfast at 07:00 am at a beautiful 6.2mmol level and I injected Novorapid basis 1:1.

Due to the low GL of my breakfast, I had a very mild spike so about 2 hours later I might have seen a spike at 8 mmols, not so bad. My diabetes nurse was happy.

However, around 09:30 (which is after my Novorapid’s peak) my BG was shooting up to 13 mmols….
“Bloody hell” I was thinking… what on earth was that?

THAT, was the low glycemic load food, which was kicking in AFTER my Novorapid had done its serious job…
As a result, at around 10:00 am, I was hoping for whatever had remained of my Novorapid (along with my Levemir overalp) to do something…

By 13:00 pre-lunchtime, I would be lucky if my BG would be at 11 mmols.

The low glycemic breakfast was messing with the timings and gave me the impression that my ratios were all wrong… I was starting to think that maybe my ratios are 2:1 or even higher.

So, I decided to experiment with a medium to higher GL breakfast of the same carbs content.

I had the same 30 grams carbs but, this time it was coconut milk, Dorset cereals, hazelnuts and berries and injected 4 units of Novorapid (just in case 3 units weren't enough).

The 1:1 ratio did work and by 11:00 am I was at 4.3mmols…

I don’t know if this is any help to you… But, maybe it isn’t your Levemir… and maybe it isn’t a ratios issue either…
Maybe it’s the glycemic load of your food?

Just a thought…
Regards
Josephine

 

[Bluemarine Josephine]

Also, I suspect that the problem is not with your Levemir’s dosage but with the timing of your evening Levemir.
If Levemir indeed lasts 14-16 hours and you inject at 18:00 then,
Your Levemir peaks around 8-10 hours later so at 02:00 – 04:00 am hence your 3.2 at 06:00 am.

If your breakfast is around 06:00-08:00 am… your evening Levemir has lost its strength and your morning Levemir has not kicked in yet as it needs 2-3 hours…

So you are left there with a weaker basal at its last hurrah and a strong dawn phenomenon…

What if, instead, you gradually move your evening Levemir injection by 1-2 hours later?
In this way you will match the Levemir’s peak to your dawn phenomenon and breakfast timing and you will have a little bit of Levemir left until your morning Levemir starts to work?

Just another thought…
Regards
Josephine

 

[DanAttw]

Yes I know they were high yesterday through fasting and normally I would have had a correction dose but I didn't want any other factors working - just the Levemir. While they were high, they were consistent expect for the morning hypo). Is the morning low not just down to the fact I had nothing to eat for 24 hours?

 

[Bluemarine Josephine]

Yes I know they were high yesterday through fasting and normally I would have had a correction dose but I didn't want any other factors working - just the Levemir. While they were high, they were consistent expect for the morning hypo). Is the morning low not just down to the fact I had nothing to eat for 24 hours?

I have never attempted a 24 hour fast (you brave person, you!) but, I would likewise suspect that, no matter how well balanced my Levemir is, after 24 hours without food it would be normal for my BG to drop.

Having said that, I also need to address the following for your consideration.

There is something called Circadian rhythm. It is what we call “the body clock”. I have attached a graph for you below.

According to our body clock, around midnight to 02:00 am our body starts to relax and as we are sinking in this deep relaxation, our blood sugar drops, our blood pressure also drops and our temperature drops too. These drops are not related to our insulin intake… it happens naturally.

Similarly, around 06:00, our blood sugar rises, our blood pressure rises (this is the reason why most strokes due to high blood pressure happen early morning hours) and our temperature also rises.

Keeping these in mind here is my theory:
Your 24 hour starvation plus,
Your natural dip around midnight – 02:00 am plus,
Your Levemir peaking 02:00-04:00 am
Lead to your 3.2 reading… it doesn’t have to be an “either or”… I think it is all these 3 combined that led to your low reading.

Personally, I think that your Levemir dosage of 12 units twice a day is well balanced.
I think the point where you ‘stumble upon” is the timing of your evening Levemir.

However, if you wish to raise the dosage of your evening Levemir in order to address the dawn phenomenon then, you most probably need a little snack just before or around midnight in order to raise your BG and avoid going too low around 02:00-04:00. Still, I wouldn't suggest this, to be honest... Chasing after your hypos while asleep is not an easy thing to do... I would prefer to experiment a little with the injection timing of my evening Levemir before resorting to the solution of raising my dosage.

I hope this helps a little…
Regards
Josephine

 

[isjoberg]

No scientific info here, having been a slave to novo rapid all my life it takes 30 mins to work in the uk on a day without exercise, 10 mins once temp is over 22 degrees or exercise has been done before - it varies which is the most useless answer.

Good luck figuring it out!!

 

[RuthW]

Ok I fasted yesterday for 24 hours on Levemir only.
The results:
6am - 12 Levemir, BG 10.8
8am - BG 12.1
11am - BG 10.4
1pm - BG 9.1
4pm - BG 8.8
6pm - 12 Levemir, BG 8.8
9pm - BG 8.2
6am - BG 3.2
So, on the whole it seems to be pretty level. The morning high is not a surprise, the dawn effect always seems to be present, although not this morning when I was low, but again not a surprise after fasting for 24 hours.
Does this tell me that the Levemir as a twin daily dose is right? It seems to.
So back to the question, why, after eating a meal, is it taking four or so hours for my levels to start to drop?

It's extremely interesting that your blood sugar rose the first morning but FELL quite dramatically the second. That implies something altogether different from Dawn Syndrome. If you ate something fairly late at night before starting the fast, and it had both high fat and protein, it can give you that kind of very delayed rise.


Sent from my iPhone using DCUK Forum mobile app

 

[RuthW]

Hello everyone!
I hope that you are all very well today!

What I am about to say may sound completely ridiculous and off topic but, there is a trick with the glycemic index.
I can see you all smiling somewhat ironically now but, just be patient with me.

Following my diabetes nutritionist’s advise, I was all for low glycemic index foods.
I was starting my breakfast, with ridiculously low glycemic load meals which included pumpernickel bread or rye bread or even the Hovis Seeds sensations and olive oil spread to delay the digestion process...

Now here is the tricky bit.
I have breakfast at 07:00 am at a beautiful 6.2mmol level and I injected Novorapid basis 1:1.

Due to the low GL of my breakfast, I had a very mild spike so about 2 hours later I might have seen a spike at 8 mmols, not so bad. My diabetes nurse was happy.

However, around 09:30 (which is after my Novorapid’s peak) my BG was shooting up to 13 mmols….
“Bloody hell” I was thinking… what on earth was that?

THAT, was the low glycemic load food, which was kicking in AFTER my Novorapid had done its serious job…
As a result, at around 10:00 am, I was hoping for whatever had remained of my Novorapid (along with my Levemir overalp) to do something…

By 13:00 pre-lunchtime, I would be lucky if my BG would be at 11 mmols.

The low glycemic breakfast was messing with the timings and gave me the impression that my ratios were all wrong… I was starting to think that maybe my ratios are 2:1 or even higher.

So, I decided to experiment with a medium to higher GL breakfast of the same carbs content.

I had the same 30 grams carbs but, this time it was coconut milk, Dorset cereals, hazelnuts and berries and injected 4 units of Novorapid (just in case 3 units weren't enough).

The 1:1 ratio did work and by 11:00 am I was at 4.3mmols…

I don’t know if this is any help to you… But, maybe it isn’t your Levemir… and maybe it isn’t a ratios issue either…
Maybe it’s the glycemic load of your food?

Just a thought…
Regards
Josephine

Yes, this happens to me too. Even to the extent that I can go hypo after eating and then see a rise later if I grit my teeth and wait it out.


Sent from my iPhone using DCUK Forum mobile app

 

[RuthW]

Another question. You are asking a general question about insulin sensitivity, not a specific one about adjusting ratios/doses etc.

Could this delayed reaction to insulin be to do with your body composition or activity levels (or both)? The better your muscle to fat ratio, the greater your insulin sensitivity is. And the more sedentary you are, the longer your insulin takes to get into circulation. I'm not asking you to tell us what your body composition is but do you realize that is a factor? (There is research that says insulin sensitivity, not HbA1c, is the single biggest factor in preventing complications and enabling longevity in people with Type 1.)


Sent from my iPhone using DCUK Forum mobile app

 

[PseudoBob77]

Another question. You are asking a general question about insulin sensitivity, not a specific one about adjusting ratios/doses etc.

Could this delayed reaction to insulin be to do with your body composition or activity levels (or both)? The better your muscle to fat ratio, the greater your insulin sensitivity is. And the more sedentary you are, the longer your insulin takes to get into circulation. I'm not asking you to tell us what your body composition is but do you realize that is a factor? (There is research that says insulin sensitivity, not HbA1c, is the single biggest factor in preventing complications and enabling longevity in people with Type 1.)


Sent from my iPhone using DCUK Forum mobile app

That's true from the reports i've read, insulin resistance/sensitivity is a major factor. Specific choices of a healthy diet and exercise improves this, our lifestyle choices post diagnosis play a significant part as well as our genetic disposition.

Sent from my SM-G900F using Diabetes.co.uk Forum mobile app

 

[DanAttw]

I know - do one thing and it throws up hundreds of variables and questions. I have a pretty healthy diet (low-fat vegetarian) and active - gym four weekdays for 35-min high-intensity training and Sunday road rides of between 50 and 100 miles. Saturday is always rest day.
My BMI is spot on (according to my doc), as is my blood pressure. Activity of course has an impact on insulin doses and how quickly it is absorbed.
Interestingly, last Sunday I did a 101-mile sportive. My BG at the start was 11.2 (at 7:15am). That's fine as I was about to burn off 5,000 calories over the next six hours. I had injected 2 Humalog 1 hour before the start (BG was 9.1) and eaten 55g of carbs. Normally my ratio is 10:1 carb to Humalog. I had decreased this by 50% (OK slightly over) to account for the imminent exercise (as per my consultant's advice).
Two hours later (after some pretty tough hill climbs), my BG was 14.9. So three hours after injecting and after constant exercise my BG was still rising. Was my ratio wrong, was my background dose too low the evening before (down from 12 to 10 or that morning - down from 10 to 8), was there a 'flight or fight' adrenaline reaction related to the increased activity or was there, as I still suspect, a delay in the Humalog taking affect?
An hour later (I stop every hour to blood test when cycling) it was 8.2, which is a massive drop and seems to be when the Humalog was starting to act (four hours after injecting).
I know there are loads of variables that could be causing this but today I got up at 5:45. My BG was 7.4. I injected 12 Levemir and only 2 Humalog as I was going to the gym for 7am. I had no breakfast. My BG was 9.9 at 7am (dawn affect?). It was 4.9 at 10am. Four hours after injecting it seems the Humalog was acting.
I'm finding the same thing after my evening meal. On Saturday (rest day) my BG was 6.4 at 6pm rising to 13.4 at 9pm! By 11pm it was down to 9.8.
On Sunday (last night) I could not excercise as my bike was in for repairs so another rest day. My BG was 7.2 before dinner at 6pm. It was 14.2 at 9pm. It fell to 9.9 at 10pm. I injected at a ratio of 10:1 and also increased Levemir to 12 (so 24 units over the 24 hours, which is my highest dose and only administered when I have nt exercised). This morning it had fell to 7.4.
This is why I am asking why it appears Humalog is not starting to act in my body until four hours after injecting. It's about the only constant thing in my diabetes at the moment. My levels are all over the place but it always seems to be around four hours before this fast acting seems to start to work.
I have ordered a Libre system and will use it for the month and use it to track my levels over a sustained period.

 

[tim2000s]

I'd say the opposite to you. You are injecting humalog and seeing a spike followed by a drop when eating. I don't think the Humalog is taking four hours to work, I think it's taking a lot less. What's happening looks like you are injecting just before eating, and you are digesting food quickly, while the insulin doesn't have a chance to catch up causing a spike. It then takes effect, whilst your glucose levels are climbing and you're seeing the overall result of the effects when you test at four hours.

I'm going to ignore your cycling, as hill climbing is typically anaerobic and will push your levels up and it will be nigh on impossible without CGM data to determine what happened.

Take your insulin an hour before eating and see what happens. On anything that is fast or medium carb, I find I need to inject Novorapid 45 mins in advance...

 

[RuthW]

I know - do one thing and it throws up hundreds of variables and questions. I have a pretty healthy diet (low-fat vegetarian) and active - gym four weekdays for 35-min high-intensity training and Sunday road rides of between 50 and 100 miles. Saturday is always rest day.
My BMI is spot on (according to my doc), as is my blood pressure. Activity of course has an impact on insulin doses and how quickly it is absorbed.
Interestingly, last Sunday I did a 101-mile sportive. My BG at the start was 11.2 (at 7:15am). That's fine as I was about to burn off 5,000 calories over the next six hours. I had injected 2 Humalog 1 hour before the start (BG was 9.1) and eaten 55g of carbs. Normally my ratio is 10:1 carb to Humalog. I had decreased this by 50% (OK slightly over) to account for the imminent exercise (as per my consultant's advice).
Two hours later (after some pretty tough hill climbs), my BG was 14.9. So three hours after injecting and after constant exercise my BG was still rising. Was my ratio wrong, was my background dose too low the evening before (down from 12 to 10 or that morning - down from 10 to 8), was there a 'flight or fight' adrenaline reaction related to the increased activity or was there, as I still suspect, a delay in the Humalog taking affect?
An hour later (I stop every hour to blood test when cycling) it was 8.2, which is a massive drop and seems to be when the Humalog was starting to act (four hours after injecting).
I know there are loads of variables that could be causing this but today I got up at 5:45. My BG was 7.4. I injected 12 Levemir and only 2 Humalog as I was going to the gym for 7am. I had no breakfast. My BG was 9.9 at 7am (dawn affect?). It was 4.9 at 10am. Four hours after injecting it seems the Humalog was acting.
I'm finding the same thing after my evening meal. On Saturday (rest day) my BG was 6.4 at 6pm rising to 13.4 at 9pm! By 11pm it was down to 9.8.
On Sunday (last night) I could not excercise as my bike was in for repairs so another rest day. My BG was 7.2 before dinner at 6pm. It was 14.2 at 9pm. It fell to 9.9 at 10pm. I injected at a ratio of 10:1 and also increased Levemir to 12 (so 24 units over the 24 hours, which is my highest dose and only administered when I have nt exercised). This morning it had fell to 7.4.
This is why I am asking why it appears Humalog is not starting to act in my body until four hours after injecting. It's about the only constant thing in my diabetes at the moment. My levels are all over the place but it always seems to be around four hours before this fast acting seems to start to work.
I have ordered a Libre system and will use it for the month and use it to track my levels over a sustained period.

LOL, we can definitely rule out insulin resistance then!

I think Tim may be right about timing.

Given the amount and variability of exercise you do, you really need a Plan (nite the capital letter!). Do you have a copy of Diabetic Athlete's Handbook? It would really help you to break your routine down and build it up again step by step for each factor, IMHO.

 

[DanAttw]

No, didn't know about the athlete's handbook but will go and get one.
My Libre system arrives tomorrow so hopefully it will give a constant graph of where my levels are going through the day and night for a month. It's a lot of money so I hope it works!

 

[Wurst]

Back to the original question , how fast is is fast acting to be ? I had recent experience which partially answers this question , at least how fast bolus acts on me.

Last week I was preparing for lunch at work, I injected the usual 3 units of humlaog bolus to cover my meal and was @ 5.5 mmol at the time of the injection. No sooner had I injected, my (big)boss came into the office and starting asking me a series of questions. This lasted for ~ 30 mins, by the time he left I felt pretty bad with classic hypo symptoms , check my BS and was @ 2.0 mmol. So in 30 mins I dropped 2.5 mmol on 3 units :-(