Oral vs. Intramuscular Vitamin B12 which is better?

Vitamin B₁₂ (cobalamin) is necessary for basic body functions, such as the growth and development of red blood cells and the nervous system. Many factors contribute to vitamin B₁₂ deficiency, such as age, blood disease, vegetarian diet, indigestion, use of drugs, as well as poor nutrition. Doctors are more likely to give vitamin B₁₂using intramuscular injection because they may be unaware of the option to use oral vitamin B₁₂ or uncertain about how well it works.Dr. Wang H and Co-researchers from Beijing University of Chinese Medicine and the Catalan Health Institute, Spain performed an analysis of 3 randomized controlled trials (RTC) to investigate whether oral vitamin B₁₂ have similar effects as intramuscular injections of vitamin B₁₂ for people with vitamin B₁₂ deficiency or not.They found that when compared to intramuscular (IM) vitamin B₁₂, oral vitamin B₁₂ has associated with similar outcomes in terms of efficacy and safety in the treatment of vitamin B₁₂ deficiency, although the evidence was deemed 'low quality'."Doctors may not be prescribing oral vitamin B₁₂ formulations because they may be unaware of this option or have concerns regarding its effectiveness," the authors write.

In the study, the researchers recruited 153 participants (74 participants to oral vitamin B₁₂ and 79 participants to intramuscular vitamin B₁₂). and the treatment duration and follow-up ranged between three and four months. The mean age of participants ranged from 39 to 72 years.

They searched CENTRAL, MEDLINE, Embase, and LILACS, as well as the WHO ICTRP and ClinicalTrials.gov for randomized controlled trials that directly compared oral and IM vitamin B₁₂. The 3 trials used for analysis included 153 participants in total (74 administered oral vitamin B₁₂, 79 administered IM vitamin B₁₂). The average follow-up period was 3–4 months.

Results from 2 trials using 1000μg/day oral vitamin B₁₂ showed no clinically relevant difference in vitamin B₁₂levels when compared with the IM formulation. In 1 trial, a mean difference of 680pg/mL favoring oral vitamin B₁₂ was noted when 2000μg/day was used. Of the 2 trials that reported treatment-related adverse events, 1 found that 2 of 30 individuals in the oral vitamin B₁₂ group left the study due to adverse events, while the other reported no adverse events in either treatment group. Additionally, oral vitamin B₁₂ demonstrated lower treatment-associated costs than IM vitamin B₁₂ in one trial (low-quality evidence due to serious imprecision).

The authors concluded that "Low-quality evidence shows oral and IM vitamin B₁₂ having similar effects in terms of normalising serum vitamin B₁₂ levels, but oral treatment costs less. We found very low-quality evidence that oral vitamin B₁₂ appears as safe as IM vitamin B₁₂.However, more trials need to be conducted that have "better randomization and blinding procedures, recruit more participants, and provide adequate reporting.

For further reference log on to :

http://cochranelibrary-wiley.com/doi/10.1002/14651858.CD004655.pub3/pdf