Lantus vs. Tresiba as Back-up

I have been on an OmniPod pump for the last 12 years, so I keep a Lantus pen as a back-up if the pump were to fail. In those past 12 years, I have had to use the Lantus only once when I accidentally brushed my PDM from a tabletop onto a tiled floor and broke the PDM. That said, I still need a back-up just in case… Now my insurance company suddenly has decided that they will not cover Lantus and want me to switch to Tresiba. I am tired of fighting them and having my doctors jump through hoops for a prescription that I probably won’t ever use. I am sure that this has happened to others. My question is, can I assume that the dosage for Tresiba will be the same as the Lantus dosage suggestion? Is there anything else I should know/consider before I agree to the switch?

You can use them interchangeably. I have used them both for vacations and activities when I don’t want my pump on, like water parks with my kid or beach etc.

It’s worth practicing though. I just take my average daily basal that my pump says and I split that to take 2 shots once in the morning once at night.

Most say you don’t need to split them but I still do it.

There is something about injecting 25 units at once that freaks me out a tiny bit.


One very safe way to translate insulin doses to another untried insulin is to deliver 80% of your former dose and then titrate up in small increments. This will minimize the risk of over-dosing but does take some discipline and patience to arrive at an appropriate dose.

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Not to argue which is a better basal, Lantus or Tresiba. It really depends on the use-case and the individual.

But, Tresiba is NOT a good replacement for a pump emergency/backup.

First of all, it takes a few days to ramp up. Second, it takes a few days to completely be depleted in your body.

For a pump backup, you need a basal that goes to work full-strength right away, not within 2 days like Tresiba.

And when you get your PDM replaced, you want the basal to be gone soon, so you can start back on the pods. You do NOT want to put a pod on and need to slowly increase your basal on the pod while the Tresiba slowly phases out.

For a pump backup, Lantus fits this bill. Tresiba does not.

If you don’t want to fight insurance, you can get a script for Lantus and get 5 pen cartridges or a vial of Lantus for about $150 from a Canadian pharmacy. They will ship it to you if you have a script. It’s legal and safe to do that, BTW. I have done it many times. It is so much cheaper.

If Lantus is only for backup, it’s not something you need to replace every month, so it’s basically a one-time cost. Despite what an expiration date might say, the fridge-life of Lantus is over 10 years.

So depending on what you want to do, I suggest either getting your endo to fight the insurance company based on the above arguments, or just get a script from your endo and pay for a cheap vial/pen supply yourself.

The worst thing to do is give in to an insurance company that does not understand the difference in the insulins, and is telling you what to use.


Like you, my insurance stopped covering Lantus so I switched to Tresiba. I actually got 24 hour coverage from Tresiba and dropped my daily dose by 10-20%,

Since then my insurance dropped Tresiba, then again picked coverage back up for Tresiba. I prefer Tresiba.

It if this all for a very temporary pump backup, I think you might prefer Lantus because it has shorter action.

If your insurance doesn’t cover your preference, your state laws or a coupon or discount card can heo with affordability’.

That is what I wanted to know. I have a well-defined protocol to follow from my Endo in the event of pump failure, so I am not in doubt as to what to do. Also, I can use my Dexcom and MDI of Novolog to keep me somewhat stable until my new PDM arrives. Insulet Corporation is GREAT about over-fighting a replacement pump when it is needed, so the use of Lantus or Tresiba would be short-lived anyway. Thanks for the response.

Thank you, Eric2. I did not know that. I will call my Endo’s office just to get clarification on what we should do. I have a supply of Lantus pens, so in a dire situation, I could use one (even though it supposedly “expired” in September 2021). If my Endo is willing to fight, I will stay with the Lantus. If not, he may need to adjust my protocol to go on and to wean off Tresiba. Sigh. Are we having fun yet? :roll_eyes:

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There are a lot of references about it, but this is a good visual showing the basic idea of why it’s flatter than other insulin’s, but also why it takes longer to be at full strength.

This image represents the idea that Tresiba is flatter once you get to the 3rd day, but it is not at 100% until the 3rd day.

Lantus is on the top, Tresiba is on the bottom.

Here is the reference link I got the image from, but there are thousands out there.


That’s surprising to hear because I have used tresiba for one day and back on my pump. With very little issues.
I run a special pump program at 50% basal for the day after.

It works pretty well with lantus or tresiba.
Not everyone has the same experience I guess.
But I also split the doses so that puts half of the basal on board at any given time.

imho, Levemir is a better substitute for basal - shorter but more reliable base line.

Maybe they made a mistake. Isn’t toujeo the biosimilar for Lantus?

Warnings and Precautions

Toujeo contains the same active ingredient, insulin glargine, as Lantus®. The concentration of insulin glargine in Toujeo is 300 units per mL.

I’ve been using NPH during failures.

Because Toujeo only comes in a pre-filled pen, the units are what counts. So if you give 20 units, the total volume of liquid injected is 1/3 of what it would be if you were giving 20 u of a 100 u/ml insulin.

Thank you to everyone for the feedback to my question. I am irritated that my non-medically-trained insurance company, with decisions based solely on money, simply decides that Tresiba will work just as well for me as Lantus. That is obviously questionable. I will take NO further action until I have a long talk with my endocrinologist about what will work the best for me. I really don’t care WHAT I have as a back-up, as long as it will work and not put my health at risk should I need it. And if that means having my Endocrinologist fight for Lantus, then that is what I will ask him to do. THANKS, everyone, for your help!

I would think if your endo writes the prescription stating it is for pump failure, it should go through. It’s not like you are getting month after month of supplies. It’s one until it expires. I would hope for less push back on that prescription. Good luck!

And I know I am in the minority here but I have been pumping since 1990 and only had one pump failure due to it hitting the tile in the bathroom while on vacation. I got the pump the next day as we were driving home the day it dropped. I called my endo & we just used regular injections throughout the day with a lot of testing. I have never had a long acting insulin as backup. We are a very resourceful group, aren’t we?! We always seem to find a way!

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There are coupons/cards available to get insulin without insurance (cash pay) when not on your insurance formulary. I get novolog using their card, 3 vials for $99. Hoping it continues in 2022. I agree that Lantus or Levemir are better choices for pump backup.

Here is one for Lantus.

Another option is to check for generic versions of Lantus.

The chart in link above, shows the generic name for Lantus is glargine.
There are 2 “bio-similars” that are glargine.
Basgalar and Semglee.

If you check goodRX website, the dropdown shows generics/biosimilar.
Your insurance may cover the generics at lower cost.

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Same here at @Sally7 , One failure and I used regular injections for the day. But I did decide to go ahead and get a back up a few years ago because it was a pain to give injections throughout the day/night.

My Lantus is expired but I know it lasts longer. I’ve used Humalog 5 years past it’s expiration date and it’s worked great.

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Sadly, most Savings Cards exclude people who are on Medicare. Ah, the joys of being over 65! :stuck_out_tongue_winking_eye:

There are some “cash pay” offers/options and don’t bill to insurance, so would not even process as MC claim.

An example of the “cash pay” option @MM1 refers to that is open to Medicare beneficiaries is the Afrezza I buy from Eagle Pharmacy in Florida. It’s $99/box of 90 doses (much cheaper than the amount billed to an insurance company) and they don’t consider any insurance and don’t exclude Medicare people like almost all discount offers from other manufacturers.