What is the toxicity of vitamin b6?

None: Vit b6 is hydrosoluble, any extra you take, it will be eliminated.

Tingling & pain: Vitamin b6 toxicity is exceedingly rare and usually only occurs at prolonged doses in excess of 500mg daily. However, some people are more sensitive to it and experience adverse symptoms at lower doses. Symptoms of toxicity include peripheral neuropathy - pain and tingling of fingers or toes. Stopping the supplement at the first sign of symptoms prevents permanent affects.