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Fiasp and Varying Sensitivity

S

StewM

Well-Known Member
Since switching to the pump recently, I've found an issue with Fiasp which was present when I was injecting it - but was quite easy to deal with - is now causing me major issues.

So when my blood sugar goes above 10 my sensitivity to Insulin drops significantly. The higher it gets the less sensitive I become. The problem is the amount of insulin it requires to get down to 6-9 is incredibly high. However, once it successfully achieves the goal of getting me back to the normal range, the Insulin on Board becomes much more potent. This almost guarantees a hypo unless I've threaded the needle incredibly precisely (something I've only been able to do once or twice).

So basically any time my Blood Sugar goes high one of two things happens. I take insufficient insulin to get below 10 and stay high for ages (like 10-12 hours), with corrections doing nothing more than stopping me going higher or reducing my blood sugar by a tiny amount. Or I take enough to get back down to normal range, but then my levels collapse once I'm back in normal range.

Whilst I was injecting Fiasp giving the Corrections would eventually get back to normal if I was patient with corrections, whereas on the Pump the differential's much higher so I can't seem to find that sweet spot.

Has anyone else encountered this issue (whether a Pump user or not) and how did you handle it?
 
I use MDI and find I'm insulin resistant with higher blood sugars and have to go down the correction route. I find if I wait until 5 hours after my first dose, my corrections are more effective and I'm unlikely to hypo later. I usually try to walk after taking them too. I sometimes need to eat something to avoid dropping too rapidly.
 
Thanks for the tag @Antje77
Yes, I still use Fiasp with my pump.
Like @StewM I find the speed at which Fiasp works depends upon my levels.
If my levels are double figures, it can take an hour for the correction to work. The challenge is to avoid rage bolusing when my levels are high and give it a chance to work without panicking. I do not notice the increased potency when my levels fall u less I have over doses.

On the other end of the scale, when my levels are in the 4s, Fiasp works immediately so I have to bolus after eating.
 
Ah, I'd avoided activity after correcting to avoid "overdoing it". So you find you get good results from coupling the correction with activity?
 
So how did you find the sweet spot?
 
StewM said:
So how did you find the sweet spot?
Click to expand...
The usual way - trial and error.
I avoid eating if my levels are in double figures until they have fallen. For this reason, I tend to look at my levels an hour before I plan to eat. This is not an issue with a CGM (Libre 2 plus xDrip+). I correct at that point if necessary and then I am ok to eat by mealtime.
If my levels are “in range”, I often use the combo/extended bolus on my pump to avoid dropping too quick, especially if I am eating a fatty meal.

As I work at a desk and my pump is controlled via a phone app, I tend to keep an eye on my levels and make tweaks if I see they are creeping up.
 
Thanks that’s really helpful.
 
I agree with many of the comments made regarding sensitivity issues with Fiasp & units required at different levels.

I have been injecting Fiasp for the past 2-3 months now and i'm on the edge of going back to Humalog. I originally changed as I dont always get time to inject a long time before meals and due to the delay with Humalog 'kicking in' it was recommended I change to Fiasp.

Due to the short acting time of Fiasp I have found I'm injecting 5-8 times a day with correction doses all over the place. I have a physical lifestyle with varying times of little / extreme excercise so routines are difficult.

I also changed from levermir to Toujeo due its long acting 'steady' working time.


It's hard to explain but when using Fiasp it seems as if it drops your mmol level with the units you provide (which can vary depending at what level you currently are) then immediatly your mmol rises with no real reason (carbs,food, movement etc) as the Toujeo seems to offer such a slow background performance.

Thanks for any advice or other peoples view.
 
I was injecting fiasp for 4 months, then overnight resistance. Woke up, usually 8 units forget about it. 32 units! I'm now 4 to 10 breakfast 14 units for 35 grams of carbs. And 2 to 10 rest of time. Switched back after a fight to novorapid and after a week it is still the same. Hoping the stuff clears out, but not looking good. Takes 4 hrs to get over breakfast, then start again lunch, been 3 weeks from hell.
 
Yeah I very much agree with your comments and those from others.

Fiasp seems to be really strange in that it lower blood sugar fine for first 2 hours but it randomly causes high blood sugar towards the end. It’s partly the reason I’m very high all the time with a HbA1c of 8.4%.

The injection site stings as well and occasionally bleeds. It’s like my body is rejecting it altogether. I did have a moment where I switched back to NovoRapid but it seems like NovoRapid doesn’t have the same effect once your body gets used to Fiasp (same insulin but Fiasp has additives which help absorption)
 
Yeah I'm finding

Yeah I'm finding that, fiasp was never quicker in morning anyway, hour and half to kill foot on floor. Still resistant, not worn off in a week. Before fiasp was eat, inject, forget till next meal. Now its maths, 2x, 1.5 x and half hour wait till the drop. Managed to get dinner and tea to just a blip on monitor, still working on morning. Just hope it wares off after a few months. If you get a hyper fiasp could kill it, novorapid its just a long wait and there is nowt that will stop it.
 
I've been on fiasp (tresiba basal) now for about 4-5 years I think.
Always been pretty happy with it's performance.
But the last week or so I'm experiencing horrendous problems trying to corrective dose from a high.
So, maybe I ate +30grams more than intended, thinking no problem I will just correction dose.
But now, what I am finding is that the corrective dose may only stabilse the high at best.
Once my bg gets into say the 14s, the fiasp seems so unreactive!
I end up taking 3 or 4 correction doses as I am just not used to having to take so much insulin in one hit.
10units is normally plenty to deal with anything over 14 but sometimes now it just doesn't touch it, so another 8, another 8 etc etc.
3-4 hours later it's down and I think blimey that took 30units in total to correct for 30g carbs
16units total is usually plenty for say a 60g meal
Once levels are back down into single figures the insulin sensitivty seems to return.
I've changed the batch of fiasp and insulin sites are decent I think (although all in the abdomen)
Very tiring and frustrating atm

Do I need an insulin change (what else is there?)

Or just more vigilance to prevent bg drifting into the teens in the first place?
 

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If you have only seen this problem in the last week, I would be checking out my insulin pens and insulin.
You could have a dodgy pen or a dodgy batch of insulin.
 
Yes new batch.
The fiasp seems OK when bg in range.
But if running high it seems so unresponsive.
 
EllieM said:
I've been using humalog for over a decade and it seems OK?
Click to expand...
Before I got used to Fiasp, I tried Humalog for a couple of weeks.
The logic was that it is different to NovoRapid so may be faster for some people.
I was not one of those people: I found Humalog even slower than NovoSluggish.
Thankfully, I was able to "train" Fiasp and have been fine ever since.

I notched it up to another case of "we are all different".

But training Fiasp has meant working a little harder to avoid the highs as much as possible.
 
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