I have read numerous articles on the efficiency of sublinguals in treatment of b12 deficiency and also seen patient testimonials lauding the efficacy of b12 pills/sublinguals. If that's the case, why r injections still considered to be superior to sublinguals? Could anyone on this forum help me understand the working of a sublingual in comparison to an injection and the difference between the two? The way I understand is that both help in elevating the b12 blood serum level but do injections ensure that b12 reaches the place where it is required (brain and cells)? My GP in US still is insisting on sublinguals and hence the question (though I m flying out next week). Also if my GP in India hands over a prescription recommending regular injections, would my GP in US comply?