Endocr Pract. 2013 Nov 18:1-36.
Kearns MD, Alvarez JA, Tangpricha V.
Division of Endocrinology, Metabolism and Lipids, Emory University School of Medicine, Atlanta, GA, USA.
Objective: Daily supplementation is often inadequate in treating vitamin D deficiency due to poor compliance. A single, large dose of vitamin D given at timed intervals may be an alternative strategy.Methods: We identified 2243 articles in PUBMED using the terms "high dose vitamin D," "single dose vitamin D," "bolus vitamin D," or "annual dose vitamin D." Review articles, cross-sectional studies, non-human studies, responses to other articles, and non-English articles were excluded.
Manuscripts were also excluded if the study:
- (1) did not use oral cholecalciferol or ergocalciferol,
- (2) used vitamin D analogs,
- (3) enrolled participants under age 18,
- (4) administered doses <100,000 IU (2.5 mg), or
- (5) administered >1 dose per year.
References of eligible manuscripts and the Cochrane databases were also searched.
Two independent reviewers identified eligible manuscripts, and a third reviewer evaluated disagreements.
Thirty manuscripts were selected using these criteria.
Results: Large, single doses of vitamin D consistently increased serum 25-hydroxyvitamin D (25(OH)D) concentrations in several vitamin D sufficient and deficient populations. Vitamin D3 doses of 300,000 IU or greater provided optimal changes in serum 25(OH)D and parathyroid hormone (PTH) concentrations. Vitamin D supplementation also impacted bone health and extra-skeletal endpoints.
Conclusions: This review recommends vitamin D3 be used for supplementation over vitamin D2, and that single vitamin D3 doses of 300,000 IU and greater are most effective at improving vitamin D status and suppressing PTH concentrations for up to 3 months. Lower doses, however, may be sufficient in certain populations. Vitamin D doses >500,000 IU should be used judiciously in order to minimize adverse events.
- Overview Loading of vitamin D note - not all loading doses are give as a single dose
- 600,000 IU vitamin D normalized virtually all seniors in 3 months – May 2012 some at-risk groups need >300,000 IU
- 300,000 IU every 3 months helped raise vitamin D levels in half of RA patients – April 2012
- Loading dose of 300,000 IU vitamin D every 6 months – Dec 2011
- 300,000 IU loading dose of vitamin D3 stopped gestational diabetes in RCT – Oct 2011
- Variety of vitamin D loading dose recommendations in the UK - 2011
- 300000 IU injection of vitamin D3 – Mar 2010 apparently injections last longer
- 600000 IU dose raised youth vitamin D level by 60 ng in 3 days – July 2010
- All Megadose vitamin D items
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