How Often Can You Get Vitamin B12 Injections? 7 Facts Vitamin B12 Injections Energy Boost The Center Medical How often should vitamin B12 injections be administered and how frequently should laboratory monitoring be performed? How Often Should You Get Vitamin B12 Injections? The Benefits Of Vitamin B12 Ugly London. Acupuncture & Chinese Herbal Medicine Gym goers spending monthly on vitamin B and C injections Have a f*cking word with yourself. Both are water soluble, so don't stick around for long in your system (12 14hrs) hence