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*Disclaimer : Speak to your healthcare provider before making any changes to your insulin regime.

Fiasp is a rapid-acting mealtime analog insulin. Manufactured by Novo Nordisk, it recently became available in India. There has been a great deal of research in the field of diabetes and over the years, different types of rapid acting insulins have been made available such as Novorapid, Apidra, Humalog among others.

Fiasp has a faster action time than any other insulin available in the Indian market
Action profile summary of different insulins 

Action time

Fiasp starts working within 2 minutes of taking it and can be taken up to 20 minutes after the start of a meal. This is because an element called niacinamide (vitamin B3) is added to the existing rapid acting insulin. The vitamin B3 helps to increase the speed of the initial insulin absorption.

Source: Diabetes Queensland


Fiasp is available as a flex pen, cartridge and vials with following specifications:

  • 1 x 10 ml vials
  • 5 x 3 ml cartridges
  • 5 x 3 ml flex-pens
Fiasp flex-pen and vial


Fiasp is priced in the same price bracket as other rapid acting insulins available in the market. It's available online too. Please check with your local pharmacy and online sites to find the best prices.

Notable points

  • It’s suitable for use for people between the ages of 18- 75 years. It cannot be used for people below the age of 18 unless a doctor recommends it.
  • It can be used by pregnant women, people who drive and women who are currently breast feeding.
  • Trials in the animal study stage (as reported by Novo Nordisk) have revealed that usage of this insulin does not impact fertility in anyway.
  • It’s advised to take your endocrinologist's advise while changing the insulin you use.
  • One unit of Fiasp is same as one unit of any other meal time insulin.
Novo Nordisk recommends the dosage time as, 'At the first bite of a meal or within 20 minutes of starting a meal.'

Possible reactions

We would like to share the undesirable effects of Fiasp listed on the information brochure and validated by some actual reviews available on the internet. This is not a general rule and the below effects (all or few) might not present themselves as you use Fiasp.

1.       Allergic reactions on the skin

2.       Severe hypoglycemia

3.       Altered dosage of insulin with usage over time

4.       Diarrhoea

5.       Back pain

6.       Upper respiratory tract infection

Video review

Video review : Fiasp insulin

Putting Fiasp to test

What sets Fiasp apart from all the other 'aspart' insulins is the faster action time. As T1s, we’ve concluded that there isn’t a one size fits all insulin available. So, we put all the claims to test! While Chhavi is a moderate to high carb consumer and uses insulin pens, Nupur advocates low carb and uses a pump.

Due to its faster action profile, it’s suitable for (very) high carb and high GI foods.

But we had to test it for low carb as well to see if it can be safely used by all our low carb readers. We have quite a few things to share with you all!

Nupur : Fiasp with low carb+pump

Read Nupur’s experience while on low carb and a pump :

I was honestly a little skeptical initially to try Fiasp for two reasons. First, I eat low carb (the typical action profile of this insulin doesn't technically match the kind of food I eat) and second, I had read stories of skin irritation and inconsistencies on Fiasp with the pump. I've also heard of slight insulin resistance over a longer duration of use and while I'm keeping a close eye, I haven't noticed it in my case yet.

In fact, I'm happy to report I've had a pretty smooth experience two months into using Fiasp. I found it pretty similar to Novorapid except that it definitely has a noticeably faster onset and peak and works upto 50% harder in the first 30-60 minutes. It's undoubtedly great for corrections. As far as mealtime boluses go, as long as I'm in range, I inject just as I eat or sometimes halfway through my meal. I often need to split my dose into two to catch the delayed protein spikes. My A1c estimate in Glimp remains at 5%

24 hrs in range - definitely a good day!

Chhavi : Fiasp with moderate/high carb+MDI

Now read Chhavi’s experience while on moderate/high carb and MDI:

I was so excited to use Fiasp, for multiple reasons but primarily for the faster action time. I do count my carbs but I’m not a LC eater by any chance. I am not a HC food advocate either. I’ve always prioritised taste over anything and while I do low carb snacking, I crave my everyday Indian food. This insulin works great if you are used to eating a regular Indian meal.

Since I used the flex pens, I had to ensure safe disposal of the flex pens also instead of just the cartridges and needles, which I'm used to.

I’m sharing below my list of pros and cons with this insulin:


  • Easier to use during office/outside meals

I’m a person with zero patience and while I’m not a 'food lover', I like being punctual with my meals and the waiting period between administering my insulin and eating food has been the most difficult thing to do as I’ve gone back to having a 9-5 job since my diagnosis. I’ve had meals where I couldn’t wait for 15 minutes because my team would have to wait with me or sometimes after injecting the insulin, my lunch would get delayed due to urgent work. For the impatient ones, this insulin is a boon! It was such a welcome change to not wait around for the insulin to start acting. Now I take my insulin exactly when we get up for lunch and I have observed lower post meal readings.

  • Lower A1C

Since the action time of insulin works well for me, keeping my BG in range has been so much easier and that has resulted in my HBA1C going down.

It's a WIP but I am very happy to be in ranges. And that reflects in a lower A1C
  • Pizza test
Yup !

This is something I was so excited to try. And since Nupur does LC, I was the one who had to do the pizza test! I hated when I learnt after my diagnosis that I wouldn’t be able to eat pizza for breakfast as I had been doing thus far. After that every time I had pizza, I couldn’t quite get the split dose right. I would spike to 300+ every single time. I didn’t have high expectations this time either. But to my surprise, the spike was relatively manageable.

That spike you see at the right, thats the pizza at work !

It even worked fine for burgers!

With burgers, the spike was very minor.

  • Great to treat hyperglycemia

Because of the fast action time, it’s a great insulin to treat hyperglycemia. I have observed improved time in range after using this insulin.


  • Rashes/Itching

This insulin did not work when I administered it on my arm (I usually use my stomach) and I felt itchy at the site. If you are going to use this insulin, please make sure you keep an eye for any rashes / itchiness.

  • Nausea

Initially for the first two weeks, I felt nauseous and light headed for a while and then as the insulin would leave my system, I would feel okay. But in the third week, the nausea disappeared and I didn’t not face any such problem after that.

  • Lack of easy availability

It's not easily available in India at the moment. Please check with your healthcare provider to see if they can arrange it for you.

Final thoughts

This happens to be the fastest insulin available in the Indian market (Afrezza isn't available here yet) and it's proven to stand tall on the claims made. Our experience has been great with this insulin so far, however since it's newly launched in India the jury is still out on it's long term impacts.

After using it for 6-8 months

Three of us who started using it around the same time found that eventually we sort of developed a resistance to Fiasp and it did not work as well as earlier and we have shared our feedback with the company as well (we have heard of a lot of others who had the same issues that it felt like water and didn't bring down highs as fast as earlier, etc.). Using it for correction alone might work better.


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