Have been to Mexico and carried the kit with me.  American Airlines insisted that I have a note from the doctor.  I carried the Solu-Cortef and syringes in my purse with the dr’s letter and was never questioned.  One thing they did also suggest is that the number of syringes you carry match the number of vials of medicine - justin case they check you.  Funny thing - we had more trouble boarding the plane for the return flight because of my daughter’s orthotics in her shoes and the stick horse she brought back!!!!