Family Practice Advance Access originally published online on April 3, 2006
Family Practice 2006 23(3):279-285; doi:10.1093/fampra/cml008
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Oral vitamin B12 versus intramuscular vitamin B12 for vitamin B12 deficiency: a systematic review of randomized controlled trials*
1 Department of General Practice, Cardiff University Wales
2 Department of Medical Biochemistry and Immunology, Cardiff University Wales
3 National Public Health Service for Wales Swansea, UK
4 Department of Medicine, McMaster University Hamilton, Ontario, Canada
5 Department of Haematology, University Hospital of Wales Cardiff, UK
Correspondence to Josep Vidal-Alaball, National Public Health Service for Wales, 36 Orchard Street, Swansea SA1 5AQ, UK; Email: Josep.Vidal-Alaball{at}nphs.wales.nhs.uk
Background. Vitamin B12 deficiency is common, increasing with age. Most people are treated in primary care with intramuscular vitamin B12. Several studies have reported equal efficacy of oral administration of vitamin B12.
Objectives. We set out to identify randomized controlled trial (RCT) evidence for the effectiveness of oral versus intramuscular vitamin B12 to treat vitamin B12 deficiency.
Methods. We conducted a systematic review searching databases for relevant RCTs. Outcomes included levels of serum vitamin B12, total serum homocysteine and methylmalonic acid, haemoglobin and signs and symptoms of vitamin B12 deficiency.
Results. Two RCTs comparing oral with intramuscular administration of vitamin B12 met our inclusion criteria. The trials recruited a total of 108 participants and followed up 93 of these from 90 days to 4 months. In one of the studies, mean serum vitamin B12 levels were significantly higher in the oral (643 ± 328 pg/ml; n = 18) compared with the intramuscular group (306 ± 118 pg/ml; n = 15) at 2 months (P < 0.001) and 4 months (1005 ± 595 versus 325 ± 165 pg/ml; P < 0.0005) and both groups had neurological responses. In the other study, serum vitamin B12 levels increased significantly in those receiving oral vitamin B12 and intramuscular vitamin B12 (P < 0.001).
Conclusions. The evidence derived from these limited studies suggests that 2000 µg doses of oral vitamin B12 daily and 1000 µg doses initially daily and thereafter weekly and then monthly may be as effective as intramuscular administration in obtaining short-term haematological and neurological responses in vitamin B12-deficient patients.
Keywords. Cobalamin, cyanocobalamin, hydroxocobalamin, pernicious anaemia, vitamin B12.
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  L. Hoey, J. Strain, and H. McNulty Studies of biomarker responses to intervention with vitamin B-12: a systematic review of randomized controlled trials Am. J. Clinical Nutrition, June 1, 2009; 89(6): 1981S - 1996S. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Chung, E. M Balk, S. Ip, G. Raman, W. W Yu, T. A Trikalinos, A. H Lichtenstein, E. A Yetley, and J. Lau Reporting of systematic reviews of micronutrients and health: a critical appraisal Am. J. Clinical Nutrition, April 1, 2009; 89(4): 1099 - 1113. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 Oral or intramuscular vitamin B12? DTB, February 1, 2009; 47(2): 19 - 21. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 N. Dali-Youcef and E. Andres An update on cobalamin deficiency in adults QJM, January 1, 2009; 102(1): 17 - 28. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 R. Lehman Evidently... Evid. Based Med., October 1, 2006; 11(5): 136 - 136. [Full Text] [PDF]
|
|
|
|
|
|
Other articles noted Evid. Based Med., October 1, 2006; 11(5): 159 - 160. [Full Text] [PDF]
|
|
E-letters:
Read all E-letters
- Oral B12 Treatment
- Sally Stabler
- Family Practice, 13 Nov 2006 [Full text]
- Oral B12 Treatment
- Josep Vidal-Alaball
- Family Practice, 13 Nov 2006 [Full text]