Did they give you a reason for the hearing loss? Did you know that people with undiagnosed Celiac Disease can have that happen? Have you been tested for that?

No, the diuretic would not "interfere" with the PFT's.

It's just that some drugs make MG worse. If, and I mean "if," the diuretic makes MG worse and you have MG, your PFT's will be worse. But it wouldn't interfere with results. Make sense?

This is going to sound stupid but it's not. Sometimes Meniere's or just plain old tinnitus or vertigo can be caused by pinching of nerves in the spine. My Mom had vertigo, had physical therapy and was better after a few sessions. She hasn't had it since. Just an example. Doctors often throw drugs right away. Not that drugs aren't useful but it's easier than trying to figure out "why" something is happening.