Bests & Worsts Reviews from Amazon

After using this product for several weeks I developed a very ugly red facial rash all around my nose and mouth. It itched and burned, and would not go away despite several creams, prescription and otherwise. I did not at first connect the rash to the high dose B12, but while desperately searching for a cause online I stumbled across several articles and studies reporting this “perioral” rash in some B12 users. Apparently in some people the B12 stimulates certain kinds of bacteria in the skin and causes them to fire up on your face. I immediately stopped the B12, and within 2 days the rash had started to clear. It has now been a week, and it is almost completely gone, except in the nasal folds. I researched some more and found that the half life of serum B12 is 6 days, meaning that it will take about 18 days for it to completely dissipate (calculating the usual 3 half lives to deplete), plus the fact that I’m also consuming some B12 in my diet. Every day the rash is noticeably better. Your skin may not be sensitive, as mine obviously is, but I offer my experience in case you have the same problem.