Hi, I have written about peripheral neuropathy many times. But, can you get CNS symptoms w b12 def? Since I started loading doses, I can no longer produce tears. I have had dry eyes for many, many years, but could still produce tears. I have read this is an autonomic nervous system issue. Also, if you get worse with loading doses, does it always get better or does it go back to baseline or can it get worse as your immune system, is in better shape? Thanks in advance.