Jillsusan,
If you were to go out in the mid-day sun clad in a bathing suit without any sun block, your skin would generate 15,000 IU/vitamin D3 in 20 to 30 minutes...
You might want to check the source of the information saying high doses of vitamin D3 are dangerous... To my knowledge after reading some of the gold standard studies on vitamin D3 dosing conducted by endocrinologists... "Even a daily dose of 40,000 IU/day vitamin D3 is unlikely to result in vitamin D3 intoxication."
What was your 25(OH)D serum concentration? Over 150 CH'ers have posted their results of using this regimen as a CH preventative over the last year... Most were taking at least 10,000 IU/day vitamin D3 and some were dosing as high as 20,000 IU/day...
So far, there have been no reports of vitamin D3 intoxication with elevated serum and urine calcium levels.
Regarding what to do... First, be aware that most neurologists and many primary care physicians are not up to speed on effective dosing levels of vitamin D3 or at therapeutic serum concentrations of 25(OH)D, the serum metabolite of vitamin D3.
Moreover, the government bureaucrats on the Food and Nutrition Board (FNB) at the Institute of Medicine (IOM) who set the at Dietary Reference Intakes (DRI) values and Tolerable Upper Intake Level (UL) use a convoluted logic to set the UL for vitamin D3 at 4,000 IU/day. It's interesting to note that the four members of the FNB who set this value are either tenured professors in biochemistry and nutrition, or long time government employees. None of them are medical doctors and none of them have ever treated patients for a vitamin D3 deficiency.
The 10,000 IU/day vitamin D3 dose is consistent with established treatments with vitamin D3 carried out by physician members of the American Board of Integrative Holistic Medicine, endocrinologists and neurologists treating patients with Relapsing/Remitting Multiple Sclerosis (RRMS).
It should be noted that the DRI for vitamin D3 was developed based on nutritional needs... The normal reference range for 25(OH)D was determined by taking a gaussian distribution (bell shaped curve) on the results of a large survey that measured 25(OH)D levels of a largely vitamin D3 deficient population, not for any therapeutic value used in treating conditions like cluster headache.
You may want to read about vitamin D3 at the vitamin D3 Council web site at:
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This is a wonderfully informative web site on vitamin D3.
One of the Jedi Masters of vitamin D3 research, Dr. Robert Heaney, M.D., developed the following chart. I've modified it with data collected from posts by CH'ers here at CH.com. It illustrates the relationship between serum 25(OH)D levels and cluster headaches at various doses.
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It's interesting to note that Life Guards in Southern California and Florida who were test for 25(OH)D all averaged 90 ng/mL, (225 nmol/L)... and none of them were taking oral vitamin D3 supplements...
Armed with this information, you should be able to make an informed decision on an effective vitamin D3 dose.
There are additional studies on this topic so please let me know if you need more information and I'll post links to them again.
Take care and please keep us posted on how you plan to proceed.
V/R, Batch