My back up is a box of Lantus SoloStar pens in the fridge, 10 bags of syringes and of course the vials of Novalog.
My endo is not only willing to prescribe the Lantus, he is in agreement that it is a better choice for temporary use than Tresiba. It is easier to go back to the pump.
I also used Lantus to boost my basal when I was receiving a steroid during chemo.
Somewhere in the bowels of FuD there is my experience with Chemo/steroids and managing BG.
Here it is. It does get off topic on various tangents that are sort of related.