I would still think that the injectible would be the best. since anything you injest is broken down by the liver and kidneys. you will probably have to injest alot more to equal an injectection.
Injectable is probably more efficient but why stab yourself when orals are readily available, very cheap, and is effective at higher dosages?
Oral vitamin B12 versus intramuscular vitamin B12 for vitamin B12 deficiency
Vidal-Alaball J, Butler CC, Cannings-John R, Goringe A, Hood K, McCaddon A, McDowell I, Papaioannou A
Plain language summary:
Vitamin B12 deficiency can cause anaemia and neurological complications. Vitamin B12 is rarely prescribed in the oral form in most countries. Two randomised controlled studies were included in this review. The trials recruited a total of 108 participants and followed up 93 of these from 90 days to four months. The evidence derived from these limited studies suggests that high oral doses of B12 (1000 mcg and 2000 mcg) could be as effective as intramuscular administration in achieving haematological and neurological responses.
I mean no disrespect to those who inject b12.
TO ME, it doesn't make sense injecting b12 everyday. Here's why:
100 tabs @ 1000mcg/tab = $6
4000mcg (4 tablets) a day = $.24
4000mcg is 666.67 times the recommended daily allowance ( 66,667% of rda). If you need more than this, you probably have other internal issues.
Oral B12 requires no syringe, no needle, no additional shots into an already tender ass, delt, or quad.
My 24 cents.
HERE IS A SMALL STUDY ON ORAL B12 EFFICACY:
Effective treatment of cobalamin deficiency with oral cobalamin.
Kuzminski AM, Del Giacco EJ, Allen RH, Stabler SP, Lindenbaum J.
Division of General Internal Medicine, Bassett Healthcare, Cooperstown, NY, USA.
Because cobalamin deficiency is routinely treated with parenteral cobalamin, we investigated the efficacy of oral therapy. We randomly assigned 38 newly diagnosed cobalamin deficient patients to receive cyanocobalamin as either 1 mg intramuscularly on days 1, 3, 7, 10, 14, 21, 30, 60, and 90 or 2 mg orally on a daily basis for 120 days. Therapeutic effectiveness was evaluated by measuring hematologic and neurologic improvement and changes in serum levels of cobalamin (normal, 200 to 900 pg/mL) methylmalonic acid (normal, 73 to 271 nmol/L), and homocysteine (normal, 5.1 to 13.9 micromol/L). Five patients were subsequently found to have folate deficiency, which left 18 evaluable patients in the oral group and 15 in the parenteral group. Correction of hematologic and neurologic abnormalities was prompt and indistinguishable between the 2 groups. The mean pretreatment values for serum cobalamin, methylmalonic acid, and homocysteine were, respectively, 93 pg/mL, 3,850 nmol/L, and 37. 2 micromol/L in the oral group and 95 pg/mL, 3,630 nmol/L, and 40.0 micromol/L in the parenteral therapy group. After 4 months of therapy, the respective mean values were 1,005 pg/mL, 169 nmol/L, and 10.6 micromol/L in the oral group and 325 pg/mL, 265 nmol/L, and 12.2 micromol/L in the parenteral group. The higher serum cobalamin and lower serum methylmalonic acid levels at 4 months posttreatment in the oral group versus the parenteral group were significant, with P < .0005 and P < .05, respectively. In cobalamin deficiency, 2 mg of cyanocobalamin administered orally on a daily basis was as effective as 1 mg administered intramuscularly on a monthly basis and may be superior. Copyright 1998 by The American Society of Hematology.
The study is not really apples to apples but it does point out that oral supplementation works.
As for bioavailability of oral b12, I have yet to find a study that gives a definite amount. I would assume that just like steroids, uptake is different from one person to another.
I just know that there is not enough food in the house when I take 2 milligrams daily
Would a pill form of a complex be satisfactory or does it need to be injectable?
No..pill form will not work as wonderful as Injection, as u know our human intestine destroy most of the vitamin (e.g calcium) injection on the other hand goes 100 % into the blood stream, B 12 is a wonderful Vitamin, you should watch if you have high blood pressure or Artherosclerosis, and other disease that u should be careful also is when u have auto imune disease such as supersensitive to allergan, since the consumption of B 12 may trigger your immune system to increase (that will be the last thing you need if you got Lupus or Arthritis)
Another day, Another challange and Opportunity