Doctor holding a vitamin B12 injection

The efficacy of different vitamin B12 supplementation methods for deficiency treatment in RYGB patients.

Vitamin B12 deficiencies are very common among Roux-en-Y Gastric Bypass (RYGB) patients. Intake and absorption of this vitamin are decreased after surgery due to absence of gastric acid and intrinsic factor, which is the carrier required for absorption. Advising the right vitamin B12 supplementation methods is essential to prevent and treat deficiencies.

Conventional deficiency treatment includes regular intramuscular vitamin B12 injections. These injections can be painful for patients and require time and effort from healthcare professionals. Therefore, this study aimed to investigate different vitamin B12 supplementation methods, to see if oral supplementation could be used as an alternative to intramuscular injections.

Vitamin B12 injections versus oral supplementation

A randomized controlled trial was conducted with 50 RYGB patients with postoperative vitamin B12 deficiencies. The level to which oral supplementation increases and normalizes low vitamin B12 concentrations was compared to intramuscular injections. In the course of six months, one patient group received bimonthly intramuscular vitamin B12 injections. A second group received daily doses of oral vitamin B12. Serum vitamin B12 was determined at four and six months after the start of treatment.

Table 1: Vitamin B12 treatment methods compared in this study

# of patients Supplementation form Supplementation dose
27 Intramuscular injection first injection 2000 mcg, thereafter 1000 mcg
23 Oral supplementation 1000 mcg daily

The effectiveness of both vitamin B12 supplementation methods

In both groups, vitamin B12 deficiencies were treated for all patients over the course of 6 months, showing no significant difference in concentration between oral or intramuscular supplementation. After 6 months, all patients had normal vitamin B12 concentrations.

Choice of treatment

Oral B12 supplementation is a good and effective treatment for deficient RYGB patients. It avoids regular injections and regular medical visits. Having this choice of treatment as healthcare professional further optimizes the care of RYGB patients.

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Schijns W, Homan J, van der Meer L, Janssen IMC, van Laarhoven CJHM, Berends FJ, Aarts EO. (2018) Efficacy of oral versus intramuscular vitamin B12 supplementation following Roux-en-Y Gastric Bypass, a randomized controlled trial. Am J Clin Nutr. 2018 Jun 21.

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