Look up the B6 toxicity information. I know I had a lot of pretty serious issues that relate to the symptoms of B6 toxicity, took FAR TOO long to get doctors to test me for it, and then when I asked what to do to reduce it.... I got a lot of blank stares and shrugs...finally one doctor said, well, don't take it anymore.
I know that for about 3 years post-taking B6 my levels dropped based on test results, but the symptoms didn't improve.
But almost all of my symptoms resolved after I started trying methylation treatment (the ones that seem to be left feel more likely ME/CFS and/or connective tissue disorder - I can't get a diagnosis either way... but it's probably down to those).
The only two things I tried during that time frame that were different from the years before when I still had symptoms were... Taking 5mg methylfolate (at the time, my dose is different now) and taking 20 minute Epsom salt baths three times a week. Within four weeks I had a dramatic improvement in the symptoms that were unique to B6 toxicity and uncommon to ME/CFS (a lot of the neuropathy, etc). Since that point in time, my ME/CFS are relapsing/remitting - but the symptoms that were unique to B6 toxicity did not return.
I've posted this suggestion before and got pointed to a couple of studies relating that magnesium helps 'use up' b6... but I don't have the links any longer.