Good Morning Rose,
Many factors may cause increased production of thin secretions. These include: infections with respiratory viruses, such as colds and flu; allergies; exposure to the cold; spicy food and medication. The treatment depends on the cause and I am thinking perhaps you need to see a third physician as the first 2 disagree on a dx for you.
I do not know if a TIF would be helpful for you. Wish I had better advice for you.
~~Kitt~~Moderator: Anxiety/Panic, Osteoarthritis, GERD/Heartburn and Heart/Cardiovascular Disease. www.healingwell.com"If you can't change the world, change your world"