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How fast is fast-acting meant to be?

D

DanAttw

Member
I'm a T1 on Humalog (and Levemir) and have been for a few years. I was put on it after using Novorapid for some years and prior to that Actrapid. But whatever 'fast-acting' insulin I use, it seems to take hours, not minutes, to start to work.
Does anyone else find this?
My consultant is adamant I am wrong and that fast-acting insulins like Humalog will start to work within 15 minutes. But I have lost count of the number of logbooks, diaries, charts from my test monitor, etc, that I've shown her that show I am having significant highs (15+) after most meals.
I have read that some people have experienced similar post-meal highs and that some even inject for a meal two hours in advance! I don't really want to do that - it sounds a bit drastic but neither do I want to continue having highs after each meal.
That said, in the mornings I now still inject as if I am having a breakfast at 6am but don't actually eat anything until four hours later. This could be down to the dawn effect and the insulin resistance we have in the mornings but it still seems to take hours for this fast-acting insulin to work.
But post-lunch and post-evening meal, I expect to see BG levels around 15 to 20 from about two hours after eating until about four hours after, when the levels begin to fall again. According to my consultant, Humalog stops working after four hours but in my body it only appears to start working then (and lasts up to eight hours).
I'm not sure what to do. Shall I start injecting hours before eating any meals and then, when I start to feel a hypo, start to eat? According to my HBA1C results, my overall control is good (6.3 in old money) but my optician has said I am showing the first signs of retinopathy and I am also getting serious foot cramps, which are signs of poor control! If I'm spending several hours every day with BG levels in the high teens, it's not a surprise. Any advice?
 
Have you actually tested your basal to see if this is the problem? If you are not having enough basal then your bolus will be doing the work of both basal and bolus insulin's.
 
Yes, I agree with CarbsRok. That's a typical pattern where your basal is too high and your bolus insulin:carb ratio is too low.


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Thanks for the replies and yes I have played around with the basal rates under the instruction of my consultants and nurses (I've moved a lot so have switched consultants several times which hasn't helped) and of course switched to Levemir. Most recently I changed from a single bedtime dose of between 18 and 24 to two doses (evening meal and breakfast) of between 10/12 and 8/12 depending on activity in the preceeding and following 24 hours.
But I am confused - one of you appears to be saying my basal may be too low and the other that it is too high.
To add to the picture, night-time hypos are not unusual - often occuring earlier in the night at around 10pm to 11pm, which is about four hours after I have had my final doses of basal and bosal. Are these hypos the result of an overdose of bosal hours before or a combination of an overdose of both insulins working in tandem?
I was told about a year ago that I needed to go on a pump and so did the training and completed the carb couting course, etc, but then was refused at the final step because the NHS said my control was good and so I didn't qualify.
I'd love to go on the pump and the Libre system but I can't afford to fund these myself. I'd love to see how my BG levels fluctuate through 24 hours rather than just seeing snapshots that my current finger prick testing provides.
I've been T1 for 25 years and this is the first time it has really, really worried me. I'm worried about the danger (both short-term and long-term) of these night-time hypos, especially as they don't wake up anymore, I'm concerned that my HBA1C results are only 'good' because they are an average of very highs and very lows rather than a consistent level, I'm worried at the contradictory advice I seem to get but what worries me the most is that I seem to be losing the ability to control this and it is beginning to contol me.
 
Hi Dan have you considered taking your evening levemir later in the evening i.e. just before bed time?
You do not have to self fund a pump the NHS pays for it. Ask for a pump and if they say no ask for the reasons.
Keep a good food diary plus insulin doses, exercise, illness hypos and present it to your team and ask how to sort it out on MDI. Then ask for a pump.
 
If you are that worried about the length of time you're high and getting complications, £150 isn't that much to get a months worth of 24/7 Libre data - which may also help provide evidence for a pump.

You mention pre-bolus'ing - it's rare doing so 2hrs before a meal, but have you actually tried it? start with 15mins before, and see what results, and change by 10mins or so each step until you find the sweet spot? (And the Libre would make that so much easier).

Getting the insulin timing right also depends on what you actually eat too, could you give us a breakdown of what you ate yesterday as an example. I'm sure you're aware of different foods have differing affects on your BGL.

But if I was you I'd do some basal testing first off.

All the best.
 
CarbsRok said:
It's an awful lot of money if you don't have it in the first place.
Click to expand...
As @slip said, £150 isn't bad providing it counts towards better control and the answer to the issue in hand.

I agree fully that it's by no means cheap, but the benefits it can give, even over just a few weeks - heavily outweigh the cost.

Grant
 
I wish I had the money. Two kids, mortgage...there's just nothing left in the monthly budget to sacrifice. That said, the blunt fact is if I don't sort this out (especially the night-time hypos) there might not be any money coming in! So I am going to try to get the funds together for the one-month trial so I can have the reliable data to work from.
I do keep a diary but only of doses and BG levels not of what I have actually eaten but I'll add that data in for the coming weeks so it will all tie in with the Libre readings.
I see my consultant again in three months, so hopefully I can convince her to get me back onto the pump list and give her the data from the Libre to work from. My gut feeling is still that the quick-acting Humalog just isn't that quick acting in my body but one step at a time.
Thanks for all your help everyone.
 
DanAttw said:
My gut feeling is still that the quick-acting Humalog just isn't that quick acting in my body but one step at a time.
Click to expand...
Have you actually done a basal test? IE., skipping meals and testing every couple of hours, this will give you the answer as to whether it's your basal or bolus causing the problems.
 
Contact your T1D HCPs they may be able to provide a reader and 1 sensor - if they don't have one get them to contact their Abbot rep as I've heard Abbot are providing some for trials - don't ask you don't get.
 
DanAttw said:
I wish I had the money. Two kids, mortgage...there's just nothing left in the monthly budget to sacrifice.
Click to expand...

Not easy when you have commitments.

Without stating the obvious but do you rotate your injection sites regularly, do you find the absorption rate varies from site to site and some are much faster than others?
 
CarbsRok said:
Hi Dan have you considered taking your evening levemir later in the evening i.e. just before bed time?
You do not have to self fund a pump the NHS pays for it. Ask for a pump and if they say no ask for the reasons.
Keep a good food diary plus insulin doses, exercise, illness hypos and present it to your team and ask how to sort it out on MDI. Then ask for a pump.
Click to expand...
after 50yrs being typ 1 and injection site problems,frozen shoulders, laser both eyes, highs and lows, severely depressed referred for a pump, was refused . as don't meet the criteria. what that means who knows... So not much chance
 
richyb said:
after 50yrs being typ 1 and injection site problems,frozen shoulders, laser both eyes, highs and lows, severely depressed referred for a pump, was refused . as don't meet the criteria. what that means who knows... So not much chance
Click to expand...
Than ask why you were refused, not meeting the criteria is not a good enough reason. Write to the consultant concerned s/he has to write back, then contact INPUT for help in securing a pump.
 
noblehead said:
Not easy when you have commitments.

Without stating the obvious but do you rotate your injection sites regularly, do you find the absorption rate varies from site to site and some are much faster than others?
Click to expand...

Yes, it is a rotation routine I have got used to - front thighs, back thighs, buttocks, stomach, back to thighs. I did try tops of arms and also lower legs but was told to stop that immediately by the nurse - she said I was injecting too close to the muscles and this could cause the insulin to act too quickly (funny, that's what I want). I tried it anyway without any discernible difference in how quickly the Humalog started to work. In fact in the lower leg it seems to take a little bit longer. As for the rest, there is no major differences.
I had a debate with my wife last night - I'm paying almost exactly the same per month into a pension that I would spend a month on funding a Libre system. What's the better investment? Will I even get to draw my pension if I don't sort this out? The joys of T1!
 
Hi @DanAttw I can sympathise with u as I used to think the sane thing. My humalog never acted as it should do so I was convinced my body was different.

Truth was it was my Levemir that was completely set at the wrong levels and in fact it was that, that was controlling my insulin. You need to get those levels sorted first and the only way u can do that is by fasting.

Do that and post your results and then I am sure people with alot more knowledge then me will be able to help
 
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?
 
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