Psilocybin reduces cluster headache attack frequency up to 50%

10 mg/70 kg, 3 doses, 5 days apart each

That is a fairly mild dose. It's enough for many people to catch a buzz, but it's not going to send them on a tour of a neighboring universe.

It's good to see a study on moderate/low dose applications, actually. The stress relief alone is probably great for a ton of other conditions, now that I think about it.