Refrigeration while traveling?

Hello everyone! I tried looking for other posts regarding this, but they’re all locked up so I can’t ask specific questions. I might take a trip in March and would need to take one dose of Zep with me. I use the vials! How would I go about keeping it refrigerated while traveling? It would be out of the fridge for approx. 8 hours and then could get back in the fridge! But I’m also seeing that once it’s out, it’s okay for a while? I would be taking my dose the second day of the trip, so not long after being out of the fridge. Any advice would be great! Thank you!