Could you have LPR, also known as respiratory reflux? If so, many people say the meds don't help them with that. Strict low-acid diet, whole foods does. There are two ENTs, Dr. Jonathan Aviv and Dr. Jamie Koufman, who have diets for GERD/LPR sufferers. When you say you changed your diet, did you change it to one of theirs? If not, here is the link to https://jamiekoufman.com, which offers info on LPR and how to deal with it. There is also a FB group dedicated to providing recipes based on Aviv's research: https://www.facebook.com/groups/199013402360712. If you have already tried the strict low-acid diet I am sorry I cannot offer any other advice based on my experience outside the usual elevate the head of the bed, chew sugarless gum, etc.