Polycystic Ovarian Syndrome (PCOS) Support Group
Polycythemia is a condition in which there is a net increase in the total circulating erythrocyte (red blood cell) mass of the body. Primary polycythemia occurs when excess erythrocytes are produced as a result of a proliferative abnormality of the bone marrow. Secondary polycythemia is caused by increases of erythropoietin that result in an increased production of...

I have currently just come back from working abroad and my friend was taking B12 as most people do over in Spain when they move there for couple months and I started taking B12 as I felt drained and it made such a huge difference I felt awake and fresh tbh but now I'm home I'm fighting with my doctor to check my levels and so on. I'm back to having no get up and go at all. I'm also on metformin. I will be taking B12 as it can do no harm as if you have to much you just wee it out.
Hope I helped.
B12, The side effects that occur, like reddening of the skin and urine and changes in heart rate and blood pressure are temporary and harmless. In short: 10 000 injections a day are still not enough for an overdose of vitamin B12.