Vitamin D and Cluster Headaches — what the evidence shows (video)
Cluster Headache Research & Study Presentation with Dr Faraidoon Haghdoost YouTube 63 minutes
🧠 Cluster Headache Research & Psilocybin Trial — Key Takeaways
Presenter: Dr. Faraidoon (Fryun) Haghdoost, Research Fellow in Headache Disorders, George Institute for Global Health / University of New South Wales
Cluster headache is considered the most severe pain in medicine — surpassing gunshot wounds per patient self-reports — yet treatment options remain critically limited. Diagnosis is routinely delayed by 8–10 years as patients are misidentified as having sinus, eye, or dental problems.
Research on cluster headache is severely underfunded. It affects approximately 1 in 1,000 people (possibly rarer), making pharma investment unlikely. In Australia, no government-funded headache disorder trial has occurred in 20–30 years, and grant success rates hover around 5%.
An Australian patient survey (n=202) revealed a heavy treatment burden: only 6% rated their treatment as "very effective," 85% reported at least one mental health condition (anxiety, depression), and 30% reported receiving no effective treatment at all. Oxygen therapy — a known effective acute treatment — was used by only 50% of respondents, largely due to access and cost barriers (~$500/month).
Patients prioritized two research goals above all else: understanding why cluster headache occurs (underlying mechanisms), and developing more effective treatments. These findings are now directly shaping the team's research agenda.
62% of survey respondents said they would join a clinical trial, and another 13% said "maybe" — strong community endorsement that helps justify grant applications for a rare disease population.
Psilocybin was the top-ranked intervention patients want studied. Prior surveys and two small trials (Denmark, n=10; US, n=8 per arm) suggest meaningful attack reduction — the US trial showed ~3 fewer attack-days per week vs. placebo, though sample sizes were too small for statistical significance.
A funded pilot trial is launching in Australia (Sydney, Melbourne, Brisbane) targeting 40 participants split into two groups: one receiving 10mg psilocybin weekly for 4 weeks in a supervised clinical setting; the other on a 4-week waitlist before crossing over to receive psilocybin. The open-label waitlist design avoids the ethical and practical problems of placebo (patients can often detect it).
The trial's primary outcome is feasibility, with secondary outcomes including reduction in weekly attack frequency, pain severity, mental health scores, and medication use. Recruitment is expected to begin by end of 2025, running for 12–14 months.
Combination therapy was also highly ranked by patients — reflecting a growing clinical logic (analogous to new evidence in hypertension management) that starting with multi-modal low-dose treatment from the outset may outperform sequential single-agent escalation.
Education of clinicians and the public is a critical gap. Patients report being denied oxygen in emergency departments, having attacks dismissed as "just a headache," and facing workplace and social stigma — all underscoring the need for systemic physician training alongside clinical trials.