I'm now twelve years in to this journey and take Mestinon daily, with IVIG every three weeks. Voice issues began for me a few months ago when my voice would just start to become softer as the day progressed or did a lot of speaking. Now it starts out fairly soft and rapidly declines to a hoarse whisper by midday and barely audible by evening.
This disease had already impacted my social life with the physical limitations caused by extreme fatigue and now I'm unable to speak over crowd noise or loud music, so even a moderately busy restaurant can pose a challenge. I had to stop physical therapy because it would just exacerbate my fatigue and my neurologist believes that speech therapy would be no more successful.