@stefspad Without knowing I was deficient, I was slowly increasing in exhaustion, heat sensitivity, heavy breathing and heart palpitations. I would get out of breath walking up stairs and have to stop midway to catch my breath while my heart was racing. Any simple activity such as basic yard work, making beds, making lunch was exhausting me to the point where I'd essentially collapse on the floor or couch as if I'd run a marathon. Bending over to pull weeds in the heat made me red faced and I'd get intense pressure in my head and migraines increased.

Once deficiency was discovered via methylmelonic blood testing (while going through SFN workup), I began B12 injections every 2 weeks then was rechecked every 60-90 days until my numbers were back to normal. After 6 months or so I stopped injections and switched to oral B12 supplements. My B12 got down to 219. Normal range falls between 200-900. Each lab can vary on numbers and 219 was enough to do damage. My Neurologist claimed this to be my underlying cause of Small Fiber Neuropathy.

I caution anyone to please be aware of signs in your body, listen and report to your Dr. immediately. Also, in my opinion B12 should be monitored regularly in everyone regardless of not having symptoms as it can permanently destroy nerves and leave you disabled.