I posted before on acquiring toxic levels of vit B6.
healthunlocked.com/mpnvoice...
B6 is unique among the B's in its potential neuro hazard at high levels. It usually reverts upon quitting but not always and it can take months. Only certain pts are prone to accumulating it as I did, I don't know any predictors.
I just got a latest test and it's finally normal. I can now say with near certainty that it was the low dose melatonin I was taking. I suggest anyone taking this sleep aid or any other supplement to check the bottle and other info for B6. It is often in melatonin at high dosage. ~1.5mg of melatonin had over 300% RDA vit B6 in it. Some supps can be well over 1000%, for example the hi potency B mixes.
Of course too little B6 is also a problem, but it's added to so many foods and supps that being low should be unlikely. Either way I suggest getting this uncommon blood test along with the more common B12 if experiencing neuropathies.