Toujeo U300 vs Tresiba U100?

I fought to keep my Tresiba but to no avail. I am going to start Toujeo soon and I take 42 units of Tresiba. Is that the same for Toujeo or do I need to adjust and go by my numbers? What has your experience been switching to Toujeo U300?

Sorry to read that you lost your effort to stay on Tresiba. I used Tresiba successfully for a few months for my last pump vacation and found it effective and simple to use. I despise non-medical switching and think that the patient’s preference should be give much more weight in this decision. Maybe you could switch back if you are unsuccessful.

I found two Sanofi (the maker of Toujeo) resources that address dosing of Toujeo. Here’s the first one I found and then the second.

Changing to a new insulin, especially one with a new concentrated formula (U300), should be managed by a doctor or perhaps a pharmacist. I’ve read about other members who were confused by this aspect and it could be dangerous, particularly if they decide to draw up a dose using a syringe instead of using the pen directly. Have you talked to your doctor about this dosing switchover?

The U300 insulin is more concentrated, so the 42 units will be 1/3 the volume of liquid.
BUT will still be 42 UNITS of insulin.
So it must be injected via the pen it is purchased with, never by syringe.

When the smaller volume of liquid is delivered, sometimes it absorbs more effectively, so a change of dosage may be required. As @Terry4 mentioned, monitor your BGs and consult with doctor to determine if changes in dose are required.