Small Fiber Poly Neuropathy can be caused by vitamin B6 Toxicity. B6 Toxicity is caused by excess B6 accompanied by a dehydrating event. Thus, the excess is not excreted in our urine. I was taking 100mg of B Complex. There was 5,887% RDA of B6. Same symptom tingling, pins and needles, numbness weakness in lower legs up to my knee. It was idiopathic with no other reason.
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