Fiasp - Major site issues - What a disappointment!

Anyone trying Fiasp and experiencing site problems?

I tried switching from Humalog to Fiasp a month ago. For the first couple of weeks the results were FANTASTIC. Very rapid onset of action. Diasend CGM downloads showed a modest reduction in average glucose levels but a big reduction in variability with only 4% of readings above 10 mmol/L (and I don’t do Low Carb). I was also able to reduce my I:C from 1:9 to 1:10 and my TDD by about 15%

Unfortunately by the third week, I began to develop site issues (reddening and bumps at the site and increasing stinging with boluses even with bolus speed changed to Slow). The problems got steadily worse and by the end of week 3, there was an obvious problem with overnight CGM readings by the second day of site insertion. By week 4 boluses were less effective and levels were pretty non-responsive to corrections.

Switching to a daily set-change relieved the problem but only temporarily. By yesterday sites were sore and swollen within a few hours of insertion. Big post-meal spikes and corrections very slow (although I could still see insulin action even after 5-6 hours). All indications of poor absorption at the site.

Since the problems were only getting worse, yesterday I switched back to Humalog and my control has settled back to where it was before Fiasp.

I am still really disappointed. Any insulin that will accommodated a large chocolate brownie without even a slight rise in BG has to be a winner. I shall miss it.

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Thank-you for this report, Joel. I’m sorry that Fiasp didn’t work for you. The “pump bumps” you describe was something I experienced using Novolog. My allergic response to Novolog came on much more slowly. I had been using it for a year or two when I started getting swelling and redness at the site. I stopped taking Novolog before it became an every-day control problem.

When people started reporting good results with Fiasp, I hoped that I could someday use it but reading your experience tamps down my expectations. I wonder if Novo-Nordisk knows what component of their Fiasp formulation is causing allergic reactions.

I’m sorry you’re having problems with Fiasp. I have really been looking forward to its approval in the US and giving it a try.

I’m sorry that you’ve had struggles using Fiaps. I’ve had ongoing problems with allergic reactions to infusion sets (not insulin or tape) and have been close to giving up pumping several times.

Have you tried a different type of infusion set (metal, angled, straight, 9 mm versus 6 mm)? Do you get the same irritation when you inject Fiasp rather than using it through a pump?

When I first started Fiasp I noticed that my ongoing site irritation/reaction problems increased a lot. But now, two months into using it, things have calmed down significantly. I recently began eating a low-carb diet again, and that seems to have helped significantly even though I didn’t notice the same with other insulins. I’m also making sure I don’t skip any allergy medications.

I have a lot of ongoing issues with allergies, and one thing I notice is that the more uncontrolled my allergies are in general, the more severely I react to infusion sets and anything else in the environment that’s irritating. If you have seasonal allergies that are acting up right now, that could be making your entire body more reactive than usual, and things may calm down later.

Hi Jen:

I also have some ongoing susceptibility to site irritation problems (although probably not as bad as you have). When I first started pumping (with Apidra), I had to go on a 2-day rotation because of rising levels on day 3. With Humalog I can get reliable absorption over 2 -days with no site irritation or soreness. With Apidra sites would occasionally start to deteriorate on day 2 but again no soreness or irritation. Therefore it seems almost certain that the problems with Fiasp are down to some sort of reaction to the insulin itself (or one of the additives). I have never pumped with Novorapid, so I can’t distingujish between the two. I can’t therefore imagine that a different type of set would make a difference. I don’t actually think this is an allergy problem, I suspect it is more an irritation due to one of the additives in Fiasp (hence the stinging on bolusing)

Injecting Fiasp might be an interesting scientific experiment but I am not planning to try it. TBH, I NEVER inject - if corrections don’t work, I just switch the set and correct again - that always sorts the problem.

It might be that if I stuck with Fiasp, Imight get used to it and the reactions might decrease. OTOH, they might just get worse, and I was in any even struggling to keep my levels below 15

BTW - I have SIX vials of Fiasp in the fridge. If anyone can figure out a way for me to send them, they are welcome to them ;-(


Picturing a pigeon flying through the air with one vial strapped to each leg…

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I had a similar (and similarly increasingly worse) reaction to Humalog when I tried it (was forced to try it by my insurance).
I tried slowing down the infusion - that helped a little - but over time, the reactions continued to get worse until I had to stop using Humalog entirely. My doctor put it in my record as an allergy. I have no similar response to Novolog or Apidra – have not yet had a chance to try Fiasp, though.

I’d love to try Fiasp (whenever the FDA gets around to approving it in the US…) I haven’t had a bad reaction to Novo Nordisk’s products, soi far, so I hope Fiasp will work – but only time will tell.

I had a week where I was getting terrible results, but I think I was just using areas for sites that have never worked well for me or that have been overused and abused. I definitely think it is worse than Humalog or NovoRapid if used in overused sites. I tried my upper abdomen this week and so far no problems. I’m on day 3 of my current site with no pain or irritation and boluses are working almost instantaneously. I also find no issue leaving it in a reservoir for a week and I’ve been outside a lot lately and the weather has been hot/humid. My biggest complaint is that the shorter tail causes higher blood sugars later on for a lot of meals. The upside is these can be prevented with using more dual wave boluses, and the shorter tail leads to way less lows I think.

Joel - It is sad to hear about your site issues with Fisap. It sounds like some sort of allergy to me.

I do not any site issues related to Fiasp.

I have been using Fiasp for two months with an Omnipod and change the pods every three days. As I mentioned in another post, I am relatively new to pumping and was having site redness and bleeding issues when I first started using Fiasp. This was similar to the issues I was having pumping with Humalog. I got a new batch of pods that have a better adhesive on the back and changed my insertion method and now I have no problems with sites.

The benefits to be have been a reduced standard deviation, a slightly lower average, and not having to pre-bolus.

Pre-Fisap I was running an average BG of about 6.8 (122) and in the last month with Fiasp I am now running about 6.0 (108).

I too am seeing highs that show up around 2.5-3 hours after the meal, but have fixed this by using extended boluses.

So interestingly, yesterday I fell off track with low-carb and ate a high-carb meal at dinner and also breakfast this morning. Because of this, I took much larger boluses than I’ve been doing on a low-carb diet and also ran +70% temporary basal rates. And I was surprised that within hours of doing this my site was itchy, and I spent all night high, went low after breakfast, and then went very high this morning and spent all day high. When I changed sites tonight, there was a huge itchy lump underneath the infusion set, almost exactly the types of reactions I was getting when I first started using Fiasp and was not eating low-carb. Yet, I’ve been finding when I eat low-carb, sites are lasting for two days no problem. It’s hard to tell how much of this is just from the difference in what I ate and my allergies in general (which have been bothering me more than usaul in the past 24 hours). But, if I didn’t know better, I’d say that it seems that the volume of Fiasp infused has an impact on how irritated sites get and whether they stop working well or not.

Has anyone noticed that Fiasp’s shorter tail makes things like feet on the floor phenomenon and after-exercise spikes more pronounced? I didn’t think this was because of Fiasp, and thought it was just my body, but I switched to NovoRapid this week out of curiosity and noticed these things have pretty well disappeared. With Fiasp I had to increase my basal immediately before getting out of bed or I’d spike fast. With NovoRapid the increased basal for my DP seems to cover me even after getting out of bed and I don’t spike. Also with Fiasp I noticed even after going on a long walk (~3-5km) I would start spiking the minute I sat down, but not with NovoRapid. I’m trying to go low-carb this week so going to stick with NovoRapid for now, but wondering if anyone else has experienced this.

Seems plausible. At the moment I am trying a little experiment. I mixed Fiasp and Humalog at a 1:4 ratio and am using that in my pump. The idea is that if on-going use of Fiasp can overcome site irritation problems, perhaps I can start desensitize myself using a mix and gradually increasing the ratio of Fiasp to Humalog. So far I managed one set over two days with a minimal amount of redness so maybe it will work.



Mixing Fiasp and Humalog seems to be working. First site using 20% Fiasp was a bit red by the second day (but nothing like it was with 100% Fiasp). By the end of the second cartridge the sites were not inflamed at all. I have now done one cartridge with 33% Fiasp (1:2 Fiasp:Humalog) with no major site problems.

Hopefully I am desensitizing myself to Fiasp. Also, 1:2 Fiasp:Humalog, seems to act very quickly and I have had to re-set my pump parameters again. Perhaps the “magic” vitamin B3 in the Fiasp is also accelerating the absorption of the Humalog. Have I invented a new insulin - Filispro?



DIY insulin (sort of), brilliant! :clap: Unfortunately, I think your approach is already claimed by Novo in this patent, which I think is about Fiasp-like compounds, so I do not think you’d be able to claim invention and seek patent protection :wink: btw, does not look like it’d be too difficult to put together a custom compound starting with whatever rapid insulin one may have at hand.

The problem with adding your own Vitamin B3 to a different analog insulin is that 1) I do not know what concentration Novo Nordisk are adding; 2) Adding any significant amount of volume will dilute the insulin ; 3) I can get hold of research quality Vitamin B3, but not pharmaceutical (suitable for injection) quality; 4) how much do I trust my sterile technique.?

In looking at Fiasp the question which needs to be asked is the risk worth the reward? The onset of action is about 6 minutes earlier and its peak is about 7 minutes earlier. It does not provide the pharma kinetics to mimic first phase pancreatic insulin release which is the holy grail for meal time insulin.

Gary Scheiner did a review available here If you are looking for fast and predictable afrezza is the way to go. Afrezza’s limitation is second phase release which is not an issue for T2s and LADA. A T1 with a CGM may need to take a second puff with slow digesting foods.

IMO Fiasp is another new product which may bring more issues than benefits but its something else for the pharma sales teams to push. Based on what was shown at ADA 2017 this year Fiasp may be the last new insulin for a long time.

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Well, a lot of us using it are Canadian and we don’t have Afrezza up here yet far as I know. The same may be true for the Europeans using it. It is definitely faster but it’s not a perfect solution by any means. I loved it at first but now I’m not so sure there is much benefit of using it if I stick to a lower carb diet with NovoRapid (Novolog). The tail is too short for me, and I find I end up with higher blood sugars later, more pronounced “feet on the floor” phenomenon, and big spikes after exercise that I don’t get with NovoRapid. It’s nearly impossible to use the super bolus technique with it for this reason too. I also find it works better in small doses, and the speed benefits start to go away when taking large doses of it.

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As @Scott_Eric said, Afrezza isn’t in Canada so isn’t an option for probably 99% of people using Fiasp. Plus, there are people like me who have asthma and other lung issues who would be nervous about using Afrezza. I certainly hope injected insulin continues to be developed.

For me, Fiasp plus low-carb eating will likely result in me hitting an A1c in the 5% range for the first time in my life.

Do you find Fiasp faster for corrections? I find IM Fiasp to be amazingly fast—an hour later I’m back in range, and I have yet to overshoot and end up low. I have a bunch of Apidra in my fridge that I have to use up, so I’m likely going to start using the Apidra for basals and the few boluses I do for meals, and then use Fiasp for corrections only.

Clearly, nothing is perfect when it comes to diabetic care. The issue with Fiasp is the risk/reward which is a personal decision. Unfortunately most of the risks will not be seen for a decade or more.

As far as afrezza its a monomer human insulin which has many advantages over the analogs for meal time use. But with a slow digesting meal a T1 will need a second dose to keep tight range to mimic second phase insulin release.

One thing which is not widely realized is a low carb/high fat diet is not the best approach with afrezza but rather a moderate carb/lower fat diet. This approach will pretty much fix the tail issue and as Gary Scheiner said he saw the 4/8/12 afrezza units equate more to his current 2/4/6. Many new user are under dosing. If you are seeing higher sugars later this is where your natural pancreatic phase 2 would kick in which as a T1 you don’t have. To mimic that another afrezza puff would be needed.

It was really targeted at the T2s but with CGMs a number of T1s are showing amazing results and nothing is better for corrections. With the T2s they are still producing insulin to cover the second phase release.

What the plans are to get it into Canada and Europe I have no idea. You would need to contact the manufacturer to see what their plans are.

Hi @George44,

I think we all agree that different insulins work better for some people than others. I am one that has great results with fiasp and others here have had not so great ones, but it is nice to hear other’s experiences.

Have you tried fiasp yet?