Hey Dr. Steve,
Welcome aboard CH.com, you've come to the right place. It's always a treat to have a physician in our midst... It's even more special as a fellow cluster headache sufferer (CH'er) who knows what we go through.
Off hand I'd say 5000 IU/day vitamin D3 is insufficient to prevent your CH... A pred taper makes it even worse...
Swing by phlebotomy and have a blood draw for the 25(OH)D lab test... I'll bet a coke & candy bar your results will come back well South of 60 ng/mL...
It turns out it's the 25(OH)D serum concentration (response) that counts... not the vitamin D3 dose.
We've well over 400 CH'ers here at CH.com who have started the anti-inflammatory regimen with at least 10,000 IU/day vitamin D3... 80% of them have experienced a significant reduction in the frequency, severity and duration of their CH. 75% of them experienced 24 hour pain free days and 60% of them have remained pain free.
The following chart developed by Dr. Robert Heaney illustrates the time course average 25(OH)D response to dose of vitamin D3.
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I've overlaid the color bands on Dr. Heaney's graphic based on CH'er posts of their 25(OH)D lab tests and CH status here at CH.com. A separate online survey of 110 CH'ers taking the anti-inflammatory regimen indicates a response rate consistent with that indicated by posts here at CH.com.
As you can see from Dr. Heaney's chart, it can take upwards of 30 days for the 25(OH)D response to reach 60 ng/mL, the bottom of the favorable response range or "green zone" as I call it.
You can elevate your 25(OH)D serum concentration a lot faster using the 4-week accelerated vitamin D3 loading schedule that squares the response curve as illustrated in the following graphic...
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The list of anti-inflammatory regimen supplements with vitamin D3 and the vitamin D3 cofactors are illustrated in the following table:
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You can find the same list of supplements along with dosing, dosing strategies, interactions and contraindications at the following link:
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I've found the following supplements shown by brand in the photo below are formulated with most of the supplements we need. I buy them at Costco, but you should be able to find similar formulations at most Vitamin Shoppes, supermarkets, Wall-Mart or over the internet:
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The accelerated dosing schedule calls for 600,000 IU of vitamin D3 plus all the cofactors over a 4 week period. The average 25(OH)D response is a gain of 60 ng/mL over the starting serum concentration. I know that sounds like a lot of vitamin D3 but it works out to an average dose of 21,000 IU/day over the 4-week period.
The dosing schedule follows:
One or two days at 10,000 IU/day just to make sure there's no reaction to the vitamin D3 followed by two weeks at 20,000 IU/day. In addition, take a 50,000 IU loading dose once a week for the first two weeks.
At the start of the third week, drop the loading dose and lower the daily vitamin D3 intake to 15,000 IU/day for another two weeks. At the end of the 4th week, lower the vitamin D3 intake to a maintenance dose o 10,000 IU/day and get another 25(OH)D lab test.
The online survey of 110 CH'ers using this regimen indicates the following response times:
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If you want to see what other CH'ers are saying about their experiences with this regimen, check out the following links:
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This isn't a one-off lark regimen... Dr. Stasha Gominak, MD, a neurologist in Texas, has been treating her migraineurs with a similar regimen of vitamin D3 for over 6 years with similar results...
You can also find a list of 40 health conditions prevented or treated with vitamin D3 all confirmed by level A RCTs at the following link:
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Take care and please keep us posted.
V/R, Batch