Bests & Worsts Reviews from Amazon

I purchased this B12 supplement because of all of the reviews. I was hoping for increased energy and vitality. I cannot overstate the importance enough for you consult your physician and test for a B12 deficiency before supplementing this. I'm writing this 20 min after leaving the emergency room due to extremely high B12 levels that caused me to have EXTREME anxiety and stomach discomfort. When I showed the ER doctor the bottle she was shocked. Even for clinical B12 Deficiency they prescribe 1000mcgs. This supplement is 5x that. When it started I almost felt psychotic...manic like. Uncontrollable anxiety and panic. I'm writing this in the hopes of saving others from the same terrible experience. I took it for 3 days before the symptoms began. And after two days I'm still not 100%. The physician said I had to wait until the b12 metabolized which could be a while. Don't take this lightly, this supplement is serious business.