Lantus vials- which way do you store?

Hi! Newbie here. My 13yo Maine Coon, Jake, was just diagnosed today. This forum has been extremely helpful so far.
I have a vial of Lantus (next time I’ll get the pen!). I’m seeing it’s important to store properly for it to last a long time. I’ve searched but can’t find which way you store your opened vials... stopper up? Or stopper down? Right now it’s sitting stopper up in the box on the top shelf of my fridge. But that means I have to turn it over each time I use it. Is stopper down better?
Thank you!

 

When I used a vial, I stored it the same way you do....in the box, stopper up.

Yes, you have to turn it over each time when you withdraw the insulin.

 

Same as Chris. I have pens now that are on the top front shelf of my refrig.