Seratonin is released by cyclical hormonal activity, and is linked to CH, which relates to periodicity of cycles and individual attacks. Also in REM sleep seratonin levels drop and that is why often people get headaches shortly after going to sleep.
Taurine acts on the thalamus, like clusters.
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I also read in a recent post which I unfortunately can't find that taurine somehow inhibits NO which is significant considering the following...
Pharmacol Ther. 2008 Aug 23. [Epub ahead of print]
The role of nitric oxide (NO) in migraine, tension-type headache and cluster headache.
Olesen J.
University of Copenhagen, Department of Neurology, Glostrup Hospital, Ndr. Ringvej 57, DK - 2600 Glostrup, Copenhagen, Denmark.
The most important primary headaches (i.e. independent disorders that are not caused by another disease) are migraine, tension-type headache and cluster headache. All primary headaches are in need of better treatments. Migraine has a prevalence of 10% in the general population and its societal costs are high. Although the precise mechanisms underlying the pathophysiology of migraine are still elusive, the last decades have witnessed some progress (e.g. involvement of serotonin, calcitonin gene-related peptide, nitric oxide, etc). Nitric oxide (NO) is a very important molecule in the regulation of cerebral and extra cerebral cranial blood flow and arterial diameters. It is also involved in nociceptive processing. Glyceryl trinitrate (GTN), a pro-drug for NO, causes headache in normal volunteers and a so called delayed headache that fulfils criteria for migraine without aura in migraine sufferers. Blockade of nitric oxide synthases (NOS) by L-NMMA effectively treats attacks of migraine without aura. Similar results have been obtained for chronic tension-type headache and cluster headache. Inhibition of the breakdown of cGMP also provokes migraine in sufferers, indicating that cGMP is the effector of NO-induced migraine. Several relationships exist between NO, calcitonin gene-related peptide and other molecules important in migraine. Also ion channels, particularly the K(ATP) channels, are important for the action of NO.
IN CONCLUSION, INHIBITION OF NO PRODUCTION OR BLOCKADE OF STEPS IN THE NO-CGMP PATHWAY OR SCAVENGING OF NO MAY BE TARGETS FOR NEW DRUGS FOR TREATING MIGRAINE AND OTHER HEADACHES. INDEED, SELECTIVE N-NOS AND I-NOS INHIBITORS ARE ALREADY IN EARLY CLINICAL DEVELOPMENT.
PMID: 18789357 [PubMed]
I would recommend you quit the excedrin, it eats your insides AND has no application for CH. Cool deal that you got a good abortive. Sounds like you've tried a bunch of pharmaceutical preventives, have you looked into any alternative treatments?
There are a few different non-pharmaceutical approaches that some people have had real success with. These include psilocybin (magic mushrooms), LSA (RC seeds), and LSD, as well as various homeopathic supplement type remedies like magnesium, Kudzu, B-2, skullcap, etc.
One or a combination of these may be able to help you reduce the frequency and/or intensity of your attacks now that you've got a dependable abortive. Some people have even been able to skip whole cycles using alternative methods.
Also, you should definitely try oxygen if you haven't yet, or even if you have. It is a highly effective and very cheap abortive that your insurance should cover and could save you some bucks on red bull (plus all that caffeine can't be too good for ya).
Good luck and enjoy the pain free days!