Jammie, Metrolamar,
Be sure to ask your neurologist or PCP for the 25(OH)D lab test. This is the serum level metabolite of vitamin D3 that's used to measure its status.
The normal reference range for serum 25(OH)D concentrations is 30 to 100 ng/mL. Unfortunately, too many physicians will say you're normal with your 25(OH)D at 31 ng/mL.
As cluster headache sufferers, (CH'ers), we need to keep our 25(OH)D serum concentration around 85 ng/mL. This ensures we're comfortably in the green zone (60 to 110 ng/L where the majority of regimen users experience a pain free response). A serum concentration of 85 ng/mL also provides sufficient 25(OH)D reserves to keep our immune system happy (It can consume 25(OH)D rapidly) and still provide sufficient reserves to prevent cluster headaches.
If your 25(OH)D is ≤ 30 ng/mL you can safely do what other CH'ers have done taking 20,000 IU/day vitamin D3 with a once a week loading dose of 50,000 to 100,000 IU vitamin D3 on top of the daily dose. An accelerated vitamin D3 dosing schedule like this will elevate your 25(OH)D into the green zone more rapidly than the maintenance dose of 10,000 IU/day.
Most CH'ers continue this accelerated dose for a week after experiencing a pain free response then drop back to the 10,000 IU/day maintenance dose. If there's no response after 30 days, drop the dose to 10,000 IU/day and ask for another 25(OH)D lab test. In either case, a second lab test for 25(OH)D after 30 days on the anti-inflammatory regimen is prudent.
I've taken both Nature's Bounty and Nature Made brands of the 5,000 IU vitamin D3 softgels and both are effective. Don't forget the 1000 mg/day Omega-3 Fish Oil and the vitamin D3 cofactors: magnesium, zinc, boron and vitamin A (retinol) at RDA doses.
The complete list of supplements and suggested doses are at the following link:
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If your neurologist or PCP gives you a ration of crap about this regimen, keep a print out of the above link handy. This regimen costs roughly 20 to 30 cents a day... It's very safe, very healthy for you and 80% effective in preventing cluster headaches equally among episodic and chronic CH'ers...
If it works as expected... get the entire family on it... See the potential health benefits at the following link:
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Doses of 4,000 to 5,000 IU/day for kids, 7,000 to 10,000 IU/day for adults and 40 to 50 IU/lb for infants appear very safe doses according to data from the above link. Again, the best indication of an effective dose of vitamin D3 is the 25(OH)D serum concentration... 60 ng/mL (150 nmol/L) for non-CH'ers.
My wife has been taking 15,000 IU/day vitamin D3 since December of 2010 and her PCP says her labs look like they came from a 25 year old woman... She kicked the heck out of 75 last Christmas and runs my backside off with all the energy. Go figure...
Take care and please keep us posted.
V/R, Batch