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Victoza to Reta advice

8 replies6 peopleSep 30, 2026☆ Follow
Summary

How to switch from long-term Victoza to Retatrutide dosing for weight loss while on insulin as a diabetic, and whether stacking with Tirzepatide makes sense

The original poster has used Victoza at 1.8 mg daily after Ozempic for 18 months with good A1C control but no weight loss, and wants to know safe starting doses of reta given their GLP-1 tolerance and insulin use. Replies note Victoza's fluctuating levels limit weight-loss results, suggest beginning reta at 1-2 mg while watching heart rate and sleep, and stress careful blood-sugar monitoring plus possible insulin reductions because reta lowers glucose strongly. Several users discuss stacking reta with tirz, with some preferring to start tirz first, while one post flags the type-1 versus type-2 distinction and need for medical oversight.

What this discussion establishesWhere people disagree

Whether to begin with reta alone or start with tirz instead, and how quickly titration can occur after 18 months on Victoza

Still open

Whether the user has type 1 or type 2 diabetes and how to manage the switch safely without physician involvement

Nothing here is advice.

8 replies · 6 people
SharpFenwick17archiveopening postSep 30

I've been on 1.8 mg Victoza every day after previously using Ozempic, totaling about eighteen months. My A1C numbers improved but weight loss stayed minimal. As someone with lifelong diabetes who still injects insulin, this approach isn't delivering results. Given the resistance and long GLP-1 exposure, would starting at 2 mg then moving to 2 mg twice weekly if needed reach a useful level around 4-8 mg? I suspect I could begin at 4-6 mg without issues. What do others think?

AmberMarble84archiveSep 30

Victoza served a purpose before other options existed. It simply does not support weight loss well, which matches what you found, because blood levels swing too much. Begin reta at 1-2 mg to gauge response, since it can raise heart rate and hurt sleep early. The 1.8 mg Victoza dose is already substantial, so faster increases should be tolerable. I am not directing anyone, but I moved from 11 mg tirz down while adding reta at 1 mg and raised it by 1 mg weekly up to 8 mg with minimal problems.

CopperSignal27archiveSep 30

The key unknown is whether lifelong diabetes means type 1 or type 2, even with insulin use, because that changes the approach and requires extra caution in type 1 cases. Some studies exist on GLP drugs for type 1 patients who also have obesity, yet they remain far from standard care. The hypoglycemia risk from GLP drugs alone stays low, but rises when paired with insulin or similar agents. Reta lowers blood sugar effectively, so frequent monitoring and insulin dose cuts will be necessary, plus ketone checks if readings look off or illness appears, since ketoacidosis can occur even in type 2. Ideally a doctor would oversee this, though reta's lack of approval may make that difficult.

BrightSparrow36archiveSep 30

Me, wondering why not tirz?

SharpFenwick17archiveSep 30
↳ replying to @BrightSparrow36

I'm wondering if combining those two would work out okay for me.

BrightSparrow36archiveSep 30
↳ replying to @SharpFenwick17

Sure, beginning with the first one feels right to me, likely since that was my own starting point, though many others lean toward the alternative. Each brings its own benefits along with drawbacks, which explains why mixing them works for me along with several people I know.

SharpFenwick17archiveSep 30
↳ replying to @BrightSparrow36

With such a long time at 1.8 mg on Victoza and 18 months total including Ozempic before, I already have Reta and plan to obtain some tirz. I’m thinking of starting Reta at 2 mg and adding 2 mg of tirz after three days if nothing is felt. The issue is I’m almost certain effects from Reta alone will not appear until 6 mg or higher.

PatientAlder89archiveSep 30
↳ replying to @SharpFenwick17

Is there some reason your physician won't write you a script for it? With diabetes your insurance cost ought to stay minimal and they could watch how things go at the same time.

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