https://www.practicalpainmanagement.com/pain/headache/intranasal-ketamine-relief-cluster-headache
https://www.biospace.com/article/releases/iv-ketamine-infusions-dramatically-improve-the-quality-of-life-for-severe-migraine-patient/
The author offers anecdotal evidence of the anesthetic agent in relieving and reducing episodic as well as chronic cluster attacks.
By John Claude Krusz, PhD, MD
Pages 36-37
Ketamine’s Mechanism of Action
Ketamine (2-chlorophenyl)-2-(methylamino)-cyclohexanone hydrochloride), a human and veterinary anesthetic agent, has an extremely varied set of pharmacologic actions depending on the dosage used.1 A selective uncompetitive N-Methyl-D-aspartic acid (NMDA) glutamate receptor antagonist, the drug has been in legitimate clinical use since 1963.
Very good article on Ketamine Use in Migraine, Cluster Headache, and Neuropathic Pain Disorders
Dextromethorphan suppresses the cough reflex by a direct action on the cough center in the medulla of the brain. Dextromethorphan shows high affinity binding to several regions of the brain, including the medullary cough center. This compound is an NMDA antagonist.
That is why I am suggesting it, and its a legal OTC compound, so my prayers and hopes would be to try to find Ketamine either by clinical trials or other means.
Just trying to help. don't mean or want anything bad