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Overview Loading of vitamin D

Loading dose: 142 studies at Vitamin D Life

If a person is, or is suspected to be, very vitamin D deficient a loading dose is typically given

  • Loading = repletion = quick replacement (previously known as Stoss)
  • Loading doses range in size from 100,000 IU to 1,000,000 IU of Vitamin D3
  • The size of the loading dose is a function of body weight - see below
    Unfortunately, some doctors persist in using Vitamin D2 instead of D3
  • Loading may be done as quickly as a single day, to as slowly as 3 months.
    It appears that spreading the loading dose over 4-20 days is a good compromise
  • Loading is typically oral, but sometimes by injection (I.M,)
  • The loading dose persists in the body for about 3 months
    The loading dose should be followed up with continuing maintenance
    Unfortunately, many doctors fail to follow-up with the maintenance dosing.
  • As about 1 in 300 people have some form of mild allergic reaction to vitamin D supplements,
    it appears prudent to test with a small amount of vitamin D before giving a loading dose
  • The causes of a mild allergic reaction appear to be: (in order of occurance)
    1) lack of magnesium - which can be easily added
    2) allergy to capsule contents - oil, additives (powder does not appear to cause any reaction)
    3) allergy to the tiny amount of D3 itself (allergy to wool) ( alternate: D3 made from plants )

Cholecalciferol loading dose guideline for vitamin D-deficient adults.

Eur J Endocrinol. 2010 Apr;162(4):805-11. Epub 2010 Feb 5.

CONCLUSION: The cholecalciferol loading dose required to reach the serum 25-OHD(3) target level of 75 nmol/l can be calculated as follows:
dose (IU)=40x(75 - serum 25-OHD(3))xbody weight.
CLICK HERE for PDF of the study, equation, and charts
To use ng and pound multipy by 35 instead of 40
    Dose to get 30 ng (in ng and pounds) = 35 x (30 - serum 25-OHD(3)) x body weight.
Typically spread over over 8 weeks
A very commonly prescribed loading dose in the US is 50,000 IU per week for 8 weeks, for a total of 400,000 IU
Example uses of the equation to achieve 30 ng (on average)

Dose starting
140,000 IU 10 ng 200 lb
70,000 IU 20 ng 200 lb
105,000 IU 10 ng 150 lb

Dose to get 50 ng (in ng and pounds) = 35 x (50 - serum 25-OHD(3)) x body weight.
Example uses of the equation to achieve 50 ng (on average)

Dose starting
280,000 IU 10 ng 200 lb
210,000 IU 20 ng 200 lb

There is a HUGE variation in response between individuals for the average (equation)

Response to 100,000 IU, 150,000 IU, and 200,000 IU vary a lot between individuals

3 day response time to a loading dose

See also at Vitamin D Life

Response with 400,000 IU loading dose @ is.gd/7DayVitD
600,000 vitamin D loading doses – good response to both oral and muscular – Oct 2015 has the following

Dose>20 ngLevel
600,000 IU IM94%30 ng
600,000 IU oral83%20 ng
200,000 IU IM88%18 ng
200,000 IU oral71%14 ng

Take vitamin D3 daily or weekly has the following
Response to a single dose of 100,000 IU starting at 27 ng/ml, half life is about 50 days
see wikipage http://www.vitad.org/tiki-index.php?page_id=1046

Pages which are in both categories: Intervention AND Loading Dose

Pages which are in both categories: Trauma/Surgery AND Loading Dose

See also web

Overview Loading of vitamin D        

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ID Name Comment Uploaded Size Downloads
8014 Loading response.jpg admin 22 May, 2017 11:08 24.22 Kb 14308
311 Loading dose guideline - April 2010.gif admin 26 Nov, 2010 18:23 16.14 Kb 49714
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