The better delivery method depends on what you are trying to accomplish and what your provider determines is appropriate for your situation
If your intake doesnt keep up with the rate at which your body uses B12, it creates a deficiency
Im mid way through my 3rd week though and I feel as though I need an increase already
People on a strict vegetarian or vegan diet or those with certain medical conditions may lack B12
Variety of Forms : There are many different types of oral B12 supplements, including chewables, sublingual (under-the-tongue) tablets, and liquid drops
[4] However, consistently taking large amounts of vitamins from multiple sources could potentially increase the risk of side effects (for example, very high vitamin B intake from multiple supplements over time can cause neuropathy, and high niacin from many sources could affect your liver)