Hey Fidelity,
Welcome to CH.com. You've come to the right place. Good questions. As the guy who developed the anti-inflammatory regimen with 10,000 IU/day vitamin D3, I think I can answer your questions.
For starters, some cluster headache sufferers (CH'ers) have very predictable cycles while others have cycles from hell that are constantly changing. That goes for both episodic and chronic CH'ers.
Regarding RCTs on the vitamin D3 regimen... here are none... other than the two surveys I've been conducting since December of 2010 and neither are published except for posts here at CH.com.
The first is a tally of responses posted here at CH.com primarily from the following link:
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To date the running tally from this link and a few others indicate nearly 500 CH'ers have started the anti-inflammatory regimen since I began posting about it in December of 2010.
At last count 80% of the 500 CH'ers experienced a significant reduction in the frequency, severity and duration of their cluster headaches... or they had a pain free response.
90% of the favorable responses occurred within the first 15 days... some in as little as 12 to 24 hours. The rest tapered off over the next month. A few took up to two months to respond.
The second source of information comes from an on-line survey of anti-inflammatory users on a dedicated survey site. Data from that survey is consistent with that collected here at CH.com with a raw efficacy of 80%.
I post results from this online survey at the following link where you'll also find all the info on the supplements used and suggested dosing:
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The real interesting data from the online survey follows:
The average 25(OH)D serum concentration for CH'ers with active cluster headaches before starting this regimen was 28.7 ng/mL, (71.75 nmol/L).
Of the 80% who experienced a favorable response to this regimen and then had the lab test for 25(OH)D, their serum concentration of this vitamin D3 metabolite was 81.4
ng/mL. (203.5 nmol/L).
What all this is saying is this evidence suggests there's a causal relationship between cluster headaches and a vitamin D3 deficiency.
This regimen is very safe, well tolerated and healthy with only a few minor side effects like an upset stomach or diarrhea, likely from the Omega-3 Fish Oil or magnesium supplements.
To date, there have been no adverse reactions reported that required medical attention. This regimen is also equally effective between men and women, as well as between episodic and chronic CH'ers.
How this regimen works, i.e., the mechanism of action remains to be proven. That said the present theory involves the autocrine path of vitamin D3 metabolism that takes place in the periphery at the cellular and nuclear level. Specifically, it involves the capacity of the active vitamin D3 metabolite, 1,25(OH)2D3, (calcitriol) to affect genetic expression by down-regulating/surpressing the production of calcitonin gene-related peptide, (CGRP) produced in nerve tissues.
I arrived at this theory on the mechanism of cation based on inference between two groups of clinical data.
In the first group, there were two or more studies that found CGRP was elevated during active bouts of cluster and migraine headaches and that it was low (normal) during non-headache periods.
In the second group there were two or more studies that concluded, vitamin D3, (calcitriol) has the capacity to down-regulate/supress the production of CGRP.
Proving this theory will require a dedicate clinical study... and the odds of that happening are quite low...
Most clinical studies are funded by big pharma... who also produce imitrex (sumatriptan succinate) and verapamil. Accordingly, why would big pharma pay for a study of an over the counter regimen of vitamins and minerals costing 20 to 30 cents a day that would endanger sales of their prescription medications for cluster and migraine headaches worth billions of dollars a year?
Finally, this regimen is not a cure for cluster headache, but it is a great preventative as long as you take it. I've been pain free of my cluster headaches since October of 2010 when I developed and started this regimen.
I'm a chronic CH'er and I've also done an intentional burn-down of my 25(OH)D reserves by stopping the complete regimen on three separate occasions. All three occasions, my cluster headaches returned after 8 days without supplemental vitamin D3... My cluster headaches also stopped as soon as I resumed the anti-inflammatory regimen.
So there you have it. If this sounds like something worth trying like over 500 other CH'ers have... see your PCP for the 25(OH)D lab test. The normal reference range for this lab test is 30 to 100 ng/mL, (75 to 250 nmol/L).
If the results of your 25(OH)D lab test come back < 30 ng/mL, and the odds are they will, talk to your PCP about starting the anti-inflammatory regimen. Show him/her a print out of the following link or send this link to him/her in an email:
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If you want to see what other CH'ers are saying about their experience with this regimen, see the following link:
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Take care and please keep us posted with your decision... and progress...
V/R, Batch