So then. 10 days after switching back to Novorapid because I was having a devil of a time with the Fiasp, I received a new prescription of the liquid that, in the US at least, is more expensive than Printer Ink (and therefore makes Gold look cheap). Time to start off with the whole shebang all over again.
Let’s remind ourselves of the marvellous qualities of this version of Aspart once again. Roughly 50% more insulin available in the first 30 mins post bolus leading to a much quicker effect, which was great while it lasted.
After the upset of last time, I’d had to determine for my own sanity, whether there was simply an off batch. I hadn’t suspected so, but still, one can never tell, so we did one more prescription. If Alliance were supplying the Novo insulin in a bad way, the first time and that was what has caused issues, then surely that couldn’t happen a second time?
Just to confirm, the insulin was received whilst at work from a fridge. It went into a fridge at work, and then was retrieved before leaving. It spent maybe an hour out of the fridge before returning home. The vial used for the pump refill came straight from the pharmacy.
And in it went.
On first use, it seemed to work well, with the rapid action that’s expected the first time I bolused. Overnight, there was a slow increase, then this morning, I had a cup of coffee. Normally I tell OpenAPS that that is 10g of carbs, and the subsequent insulin delivery manages the Ephidrine linked blood glucose rise.
This is best reviewed by taking a look at the below picture:
So let’s look at the blue box. That’s Fiasp as I expect it to work. No pre-bolus, very quick action and allows me to run just off Super-Micro Bolusing. And a welcome return too.
However, the orange box. That’s where we see things misbehaving. You can see in the IOB pill that there are 3u of IOB. There was a 2u bolus at 9.30. That means that following the 10g carb equivalent entered for coffee, OpenAPS and I had given me 4.8u of insulin as SMBs and a bolus. With an overall change in glucose level of about +2mmol/l. Now by my reckoning, that’s suggesting an IC ratio of something in the order of 4u per 10g of carbs, or 1:2.5. And we’re not down yet.
It looks as though the issues I was seeing at the end of the last period have not been resolved with a ten day use of Novorapid.
The final test in this process is that 2u bolus at 0930. If the Fiasp is working as it should, I’d expect to see a steep drop commencing within the first hour after the delivery of the insulin, and a drop of around 4mmol/l that will need intervention, as I should see glucose levels drop below 4.0mmol.
Instead, we have this:
As the purple box area shows, whilst still fasted, a 2u bolus (plus whatever else was onboard) has lowered glucose levels by what amounts to not a lot – 7.5ish to 5.8. A drop of only 1.7 mmol/l. This equates to an ISF of around 0.85mmol/l/1u, which would also equate to a Carb Ratio of 3.5u/10g carbs.
I think that it’s fair to say at this point that this is not acting quite as the original hype, or my own for six months, suggested it should. As a matter of fact, it’s not even acting like regular Insulin Aspart (Novorapid).
But anyway, leaving it for a further two hours results in a further drop, some of which has to be attributed to the decision from OpenAPS to SMB when the curve flattened out.
Now by this point, I’m hungry, and lunch is looking interesting, but I’m in a quandary. Do I try and bolus with these ridiculously insensitive ratios that seem to be generated, or do I syringe Novorapid?
Well it depends on the hypothesis I’m following. If it’s that my liver isn’t responding to Fiasp, or that I have localised sensitivity, then, yes, okay, that makes sense, but what if it’s something else?
Let’s suggest that it’s an immune response or insulin pooling, which the above graph could also be suggesting. If it’s that, then doing a bolus at these ratios isn’t like to stop a lunch rise, and more importantly, is likely to cause a significant drop well after I’m expecting it.
So, in the name of “Science” and with some careful observation going on here, that bolus was done with the ratios calculated earlier. A 1u/4g of carbs, with the knowledge that there is a 60g protein load on at the same time. What we see seems much more akin to the effects of Fiasp that I’ve previously seen. Both the ISF and Carb Ratio in my pump have been adjusted and OpenAPS is using those to calculate its adjustments.
The updated values, for now are least, seem to be working.
This does lead me to suggest there is some form of insulin resistance going on, whether that’s local to the cannula site or generally, and that potentially what I previously saw when I thought things were going horribly awry was this having an effect and not enough insulin covering both glucose absorption and some level of incretin effect generating glucose from the liver.
In fact, the last 24 hours aren’t too bad. With the exception of the over announcement of a meal in the evening, resulting in a low that needed to be treated (which would have been the same if I had manually bolused), what I’m seeing is that the Fiasp seems to be acting as expected in terms of its action time.
The latest dialled in settings, with a day of observation, i.e. not really long enough, seem to suggest that there’s been a quantum change in mealtime insulin need (I note there is less of an issue on basal, although a slight one) more than anything else.
So the question is, do I continue in this new land of much higher insulin need, or do I give up on it and go back to Novorapid? I still like the fast action of the Fiasp, but is it healthy to be reaching a TDD amount which is starting to look like the doses given to someone who is suffering the early identifiers of double diabetes?
If we look at how my insulin sensitivity factor has changed, it looks like this:
And what about the costs? Such an increase in insulin usage results in 10ml phials being consumed every 11-12 days instead of every 21-22 days. That may mean the per volume unit cost is the same as Novorapid, but it also means the required use cost is double.
Whilst I am sure there are people out there who are happily using Fiasp with no issues, there’s been a lot of noise amongst social media sources that raises questions. It’s clearly not easy to switch to and changes happen irregularly and inconsistently. I’ve got a ton of data, a set of tools and a loop to help me manage this. Without them, it would be a nightmare. As others have found.
So with Fiasp, what goes up does eventually come down. The only question is whether you can predict when that is likely to be.