Brew's comments on vitamin D3 dosing, 25(OH)D serum concentrations and vitamin D3 toxicity are spot on!
A recent study titled
Vitamin D Supplement Doses and Serum 25-Hydroxyvitamin
D in the Range Associated with Cancer Prevention by Garland, French, Baggerly and Heayey concluded that: Universal intake of up to 40,000 IU vitamin D per day is unlikely to result in vitamin D toxicity.
VitaminDwiki has a number of excellent charts like the following on vitamin D3 dosing and loading doses to achieve a target 25(OH)D serum concentration of 50 to 70 ng/mL...
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It's important to note that this 25(OH)D target range is for normal people... As CH'ers... we're far from normal as Brew pointed out.
We suffer from a condition characterized by neurogenic inflammation... and so far, the data we've collected here at CH.com and from the online survey of CH'ers using the anti-inflammatory regimen with 10,000 IU/day vitamin D3 indicate we need an average target 25(OH)D serum concentration around 85 ng/mL ±10 ng/mL to remain pain free of cluster headaches.
It is also important to note that we are way out in front of conventional medical science dosing on vitamin D3 at 10,000 IU/day in order to maintain an average target 25(OH)D serum concentration of 85 ng/mL to prevent our cluster headaches.
There are no other RCTs on this topic. The best and only information on the safety and efficacy of the anti-inflammatory regimen with 10,000 IU/day vitamin D3 is right here at CH.com. So far since December of 2010... I'm unaware of any reports of adverse reactions to this regimen that required medical attention... and the efficacy is holding steady at 80%.
I've done some recent reading on an RCT reporting the efficacy of verapamil as a prophylaxis for episodic cluster headache sufferers... See attached pdf file for more info.
Verapamil reduced attack frequency and the use of abortive agents in episodic cluster headache
Design: Randomised {allocation concealed*},† blinded {clinicians, patients, and outcome assessors*},† placebo controlled trial with 2 week follow up.
Setting: 3 outpatient clinics in Italy.
Patients: 30 adults between 18 and 60 years of age (mean age 44 y, 90% men) who were outpatients and had a diagnosis of episodic cluster headache (International Headache Society criteria) with > 1 previous cluster period lasting > 1 month and who had been in a cluster period for < 10 days and had an expected duration of the remainder of the cluster period of >20 days.
Exclusion criteria were liver or kidney disease, cardiopathological findings contraindicating verapamil use, psychiatric disorder, use of antidepressants or antipsychotics, drug or alcohol abuse, or previous adynamicileus. Follow up was 100%.
Intervention: After a 5 day run in period, patients were allocated to verapamil, 120 mg 3 times/day (n = 15), or placebo, 3 times/day (n = 15), for 2 weeks.
Main outcome measures: Self reported frequency of cluster headache attacks and use of abortive agents.
Main results: During the first week of treatment, the verapamil and placebo groups did not differ for median numbers of attacks/day (1.1 v 1.7) or abortive agents used/day (1.0 v 1.2).
During the second week of treatment, verapamil was more effective than placebo in reducing both the number of attacks (median 0.6 v 1.65/d, p < 0.001) and the number of abortive agents used (median 0.5 v 1.2/d, p < 0.004). Fewer patients in the verapamil group than in the placebo group were non-responders (ie, having a < 50% reduction in attack frequency) {p < 0.001}. Side effects experienced during the treatment period were mild.
Verapamil v placebo for prophylactic treatment of episodic cluster headache at 2 weeks
Outcome Verapamil Placebo RRR (95% CI)
Non-response 20% 100% 80% (53 to 93) 1 (1 to 2)
Because this RCT was done to the gold standard: randomized, blinded, placebo controlled... it carries more weight as medical evidence than our online survey of CH'ers.
Data from that survey indicate 80% of the 75 paticipating episodic CH'ers experienced a favorable response with a significant (>50) reduction in the frequency, severity and duration of their CH and 62% experienced a sustained pain free response.
Most of the CH'ers in this survey who experienced a favorable response experienced that response in first week.
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You can draw your own conclusions...
Take care,
V/R, Batch