MrsD, thanks again for the info. This is an update while I wait and prepare for my next appointment on Oct 28th. I will pursue the possible Levaquin cause, my upper end TSH numbers, A1C testing, and small fiber function, with him. He said he will focus on the small fiber function which hopefully will lead him to those potential causes. In the meantime I started the B12 methyl-cobalamine on Sep 16 (5000 mcg/day) and quit on Sep 21 because of palpitations. The palpitations stopped 22 Sep (unless I was just so sleep deprived I slept through them). I restarted the B12 on Sep 23 thinking there might have been some other reason for the palpitations but, unless it’s all in my mind, they started again and I stopped the B12 again yesterday. Can the palpitations be due to something else? thyroid? It’s frustrating because even after a few days I could sense my nerve condition was improving slightly with the B12, not as much pain, less numbness for longer periods. The nights after I stopped taking the B12 were bad with sharp pains in my toes, hot feet. I’m thinking of starting B12 again but in 1000 mcg/day. It was working with 5000 mcg, but I couldn’t sleep with the palpitations. I started fish oil on Sep 23. I applied the CVS Epsom Lotion to my feet twice in the past week and it makes them feel better. I want to begin the ALA, ALC, or Ubiquinol but I haven’t yet because I didn’t want to attribute any side effects to the wrong supplemental, if that makes sense. I wanted to get the B12 working without the palpitations. I’m tempted to start taking them anyway because the sooner I start, the sooner I hopefully would see results.