Taking high dosage becomes mandatory as a treatment because of age, vegetarian diet and predisposal because of certain medical conditions. Some medical conditions that can prevent the absorption of this vitamin are diabetes, peptic ulcer, hyperacidity, dysfunctional pancreas, etc. If you are leading an unhealthy lifestyle, it may best that you
buy vitamin B12 just to make sure. It will make things easier and more convenient.
If you must really
buy vitamin B12, know where and what to buy. Seeing a doctor can make deciding even easier and precise. Where to buy is actually not the problem; it is distinguishing the good sources which is more daunting. Do not deviate from the prescription. Take not of the dosage and buy the same formulation so that you need not make any adjustment and for better compliance. It is also important to look into the credibility of the manufacturer to make sure the quality is not compromised. The last to consider is really the price. Discounts are usually given for products on special promotion. It will be important to determine first if such is something that meets the standard of your prescription before buying so many bottles you may regret buying later.
After all this fuss, you can relax even if you sometimes miss the taking the supplement after all a certain fraction is actually saved in the liver to last you 20 or more years..