Thank you so much for the verification of my post and it seems that you have a clear understanding of whatever I have begin and you also agree with me that injecting medicine into veins is more effective than to take it through oral way and through mouth as well as you have also an idea that if you are digestive system is weak then many of the drugs you cannot absorb and specially according to this engagement challenge question vitamin B12 should be absorbed through injections and is specially in those people who are in older age.....