I would call the airline that you are using directly. Every airline is different and you never know now a days what they will or will not let pass. Some will not let you pass the ice packs or ice. I know it is for medical reason so they are probably more likely to let it pass but I have a friend who has a baby and she went on a business trip and they would not let her bring her ice pack to store her breast milk and they also made her dump the breastmilk out that she had already pumped. It is also different at different airports. You have to go thru so much security and it is not only for one airline it is for many so I would ask that they send you a ticket that has that you are traveling with medication that needs to be keept cold. I had a ticked that requested a cart to take me to my conecting flight because I knew that there was no way that I would be able to do that with my two kids (one an infant) and have time to do her breathing treatment. I just had to show it to someone as soon as I got off the plane and they had one ready for me. I travel a lot internationaly with my kids so I know how important it is to have everything in order before you head out. Good luck and have fun on your vacation.