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Update on the evidence for oral B12 supplements to treat deficiency

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Review of: Wang H et al. Oral vitamin B12 versus intramuscular vitamin B12 for vitamin B12 deficiency. Cochrane Database Syst Rev 2018;3:CD006897.

Key learning points

  • Low-quality evidence confirms previous finding that oral vitamin B12 may be as effective as intramuscular B12 injections for treating deficiency.

  • High doses of oral vitamin B12 may be better at increasing serum B12 levels, but this was based on a single small study.

  • The costs of treatment in the oral vitamin B12 group were lower than in the intramuscular group.

There is low-quality evidence that high dose oral vitamin B12 (1–2mg/day) may be as good as intramuscular vitamin B12 with no difference in adverse events.


This update to an earlier Cochrane …

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  • Conflict of interest None declared.

  • Provenance and peer review Commissioned; internally peer reviewed.

  • Contributors DTB Team.