I am sorry you have this cough. I don't have an answer for this but when I saw your post I asked my Dad who is a Internal Medicine Doctor. He agrees with a few of the other members here that Mucinex DM is the way to go to help with the cough. If there is an infection in your lungs then you probably need to get on a regiment of an Antibiotic. I guess you are currently on vacation at WDW which may make this option really difficulty but he said have you tried a vaporizer machine using water vapor and Vicks vapor rub in it. If you can get one have this positioned at night to blow towards you face. My dad says breathing in this vapor will help you breathe properly and limit that annoying cough. I hope you feel better soon. It sucks being sick at WDW.