New insulin phenomenon? (Tresiba to Lantus)

So I switched from Tresiba back to Lantus, and my daily basal dose has dropped. A lot.

I remember that when I switched from Lantus to Tresiba I kept the same daily dose (maybe ±1 unit).

I remember reading other’s posts about how there’s often immediate success and sensitivity when you switch to a new insulin. I’ve used Lantus before, but it’s new at the current time. Is it possible that the new insulin phenomenon could explain why I’d need so much less insulin than I expected?

The first week was super messy because Tresiba lasts so long for me, and I’m not counting that week at all. I’m past 2 weeks now, so the Tresiba should be completely gone.

I was taking 24 units of Tresiba at this time of the month - might’ve needed 23 at times, but I couldn’t change it that easily, so 24 was as low as I usually went. Yesterday my Lantus dose was 21, and today I’ll lower it to 20. Maybe Lantus and Metformin work together “better” than Tresiba and Metformin?

I’m waiting to voice my opinion on the switch to Lantus until after I’ve gone through the more difficult time of the month with only Lantus in my system. That’ll be in a couple weeks. I always love the current time of the month. It’s all flat lines and uber-sensitivity.


What caused you to switch, if you don’t mind my asking?

There are a few reasons, but they’re mostly related to not being able to quickly change my dose. Any changes in a dose weren’t really visible until 24 hours after a dose change.

This was especially evident when I switched off Tresiba. I decided to wait to give my first dose of Lantus until I started to see an upward trend. That upward trend didn’t occur until 18 hours after I should’ve given my Tresiba dose. And that’s for a dose that’s been entirely missed. The impact of a 1 unit change would clearly be different. I’ve read other’s posts on Tresiba, and it seems like they see the results of changes so much sooner.

This problem made traveling a lot more challenging. Going from a 10 hour plane ride (where I always run high) to walking 20,000-30,000 steps a day creates a basal nightmare when you can’t switch your basal from one day to the next. Then after eating the high carb, high fat pasta and pizza in Italy for a few days, my basal needs rose higher than they were before the trip! Even though I was still walking 20,000 steps a day. I just really wanted to be able to change my dose and see immediate results.

When I talked to my doctor about it, he asked about lows. I didn’t have a lot of lows on my AGP report, but I did spend portions of the month treating “lows” before they occur because I couldn’t adjust my basal dose quickly for changes in basal needs due to my monthly cycle or exercise.

He suggested that I may have gained weight since starting Tresiba because of this problem. That perhaps I’m having more carbs than I used to at times that I wouldn’t have in the past. He also said that everyone responds differently to different insulins and Tresiba may not have been a good fit for me personally.

I have no idea if Tresiba itself can cause weight gain, but the timing of when I started gaining weight definitely correlates with my switch to Tresiba. Whether it’s Tresiba itself or my inability to vary my doses easily doesn’t really matter. If part of the reason I gained weight is somehow attributable to Tresiba, I wanted to stop using it.

So I suppose the main reason I switched is so I can vary my doses when my basal needs change so that I can enjoy traveling and working out (and the 24 hours afterward), and treat fewer lows.


Makes sense and quite enlightening, on why it is better to have multiple tools available to the diabetic community. Since the tool that works really really well for one person, may not work that well for the next. Thanks for sharing.


Makes sense to me—that’s my one major issue with Tresiba, and if I had more variable activity levels, I don’t think I’d stay on it, because there’s no way I can adjust adequately the rare times I do. Same thing if I hadn’t mostly stopped drinking alcohol and did so often and variably.


So there was some kind of phenomenon, but it faded. I eventually settled on 23 units during the high point of my monthly cycle and 22 units during the low point. This is still lower than the Tresiba.

I’ve also started losing weight. For whatever reason, Tresiba was a really bad fit for my body type.

My control on Lantus and Afrezza is better than my control on Tresiba and Afrezza too. I wish I had switched back sooner. The first few weeks I had more lows, but I’ve locked things into place now. The nights have been great. I’m hoping that and the weight loss will continue.