Pharmacokinetics and effects of demographic factors on blood 25(OH)D3 levels after a single orally administered high dose of vitamin D3.
Acta Pharmacol Sin. 2016 Nov;37(11):1509-1515. doi: 10.1038/aps.2016.82. Epub 2016 Aug 29.
Chen PZ1, Li M1, Duan XH1,2, Jia JY3, Li JQ1, Chu RA1, Yu C3, Han JH4, Wang H1,2,4.
Overview Loading of vitamin D contains the followingLoading dose:
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 )
- Loading Dose of Vitamin D category listing and associated searches
- Children in Intensive Care need Vitamin D loading dose of 10000 IU per kg (nearing a consensus) - Oct 2016
- Inflammation reduced by a single dose of Vitamin D (200,000 IU) – RCT Jan 2016
- 500,000 IU of vitamin D cut in half the hospital days following a lung failure – RCT 2015
- Vitamin D loading doses of up to 400,000 IU OK for adolescents – meta-analysis Dec 2014
- Large dose of vitamin D (200,000 IU) lasts for about 100 days – Feb 2015
Note the large variation in the individual responses
- some got much higher than mean response
- some got virtually no resonse
see Reasons for low response to vitamin D - includes
poor health, very deficient, obese, poor liver, poor gut, gallbladder removed, old age,
To examine the biological consequences and demographic factors that might affect the pharmacokinetics of vitamin D3 after a single high dose intervention in a young Chinese population with vitamin D insufficiency status.
A total of 28 young subjects (25 to 35 years old) with vitamin D insufficiency status [serum 25(OH)D <30 ng/mL] was recruited in Shanghai, China. The subjects were orally administered a single high dose of vitamin D3 (300 000 IU). Baseline characteristics and blood samples were collected at d 0, 1, 2, 3, 7, 28, 56, 84 and 112 after the intervention. The blood biomarker levels were determined with standardized methods.
The intervention markedly increased the blood 25(OH)D3 levels within the first five days (mean Tmax=5.1±2.1 d) and sustained an optimal circulating level of 25(OH)D3 (=30 ng/mL) for 56 d. After the intervention, body weight and baseline 25(OH)D3 levels were significantly correlated with circulating 25(OH)D3 levels. No adverse events and no consistently significant changes in serum calcium, creatinine, glucose, parathyroid hormone, vitamin D binding protein, or the urinary calcium/reatinine ratio were observed. However, there was a significant increase in phosphorus after the vitamin D3 intervention. Total cholesterol and triglyceride levels were decreased at the end of the trial.
The pharmacokinetics of vitamin D after intervention were influenced by baseline 25(OH)D3 levels and the body weight of the subjects. The results suggest that a single high oral vitamin D3 intervention is safe and efficient for improving the vitamin D status of young Chinese people with vitamin D insufficiency.
PMID: 27569392 DOI: 10.1038/aps.2016.82 Publisher rents PDF for $4