Has anyone with a moderate to high panic disorder traveled outside their country? I want to travel for 2 weeks but it requires a long flight (approx 18 hrs for one flight then another 11 for another destination)

I have somehow miraculously travelled to Europe 10 yrs ago popping only one pill. I’ve no idea how I did it then. Then since I have done 1 hr flight and cried begging it to be over. 

I would travel with a good friend who does understand but worried I will spend the entire time medicated to just get through my days (though currently am only on anti depressants no anxiety meds at all)