Quickly, more later.
For the fibromyalgia case, please consult THE book: What your doctor may not tell you about Fibromyalgya, by R. Paul St.Amand, MD.
The guy is the major responsible, if not finder, of the use of guaifenesin to open up renal conduits and thus allow excretion of phosphates. He also mentions this is a genetic defect. He know what he is talking about: he has it, and so do his children.
Thanks for the web reference, but they don`t ship to Canada anymore.