do you have megaloblastic anaemia? had any gastric surgery (ie no intrinsic factor to secrete to absorb B12 from the ileum)? then why would you want a B12 injection? i honestly dont understand why people think this is going to boost them with energy. if i remember correctly neurobion is a mix of B12, B6 and B1. pop a pill if you must (if you follow a healthy diet then this wont even be necessary). neurobion burns like a [expletive]. the best cure for being tired, is really dumbed down basics: sleep more, stress less (impractical advice, i know), drink more water, eat less super refined carbohydrates (sugar sugar sugar).