Psychedelics are usually known for many things: making people see cool fractal patterns, shaping 60s music culture, healing trauma. Neuroscientists use them to study the brain, ravers love to dance on them, shamans take them to communicate with spirits (or so they say).

But psychedelics also help against one of the world's most painful conditions — cluster headaches. Cluster headaches usually strike on one side of the head, typically around the eye and temple, and last between 15 minutes and 3 hours, often generating intense and disabling pain. They tend to cluster in an 8-10 week period every year, during which patients get multiple attacks per day — hence the name. About 1 in every 2000 people at any given point suffers from this condition.

One psychedelic in particular, DMT, aborts a cluster headache near-instantly — when vaporised, it enters the bloodstream in seconds. DMT also works in “sub-psychonautic” doses — doses that cause little-to-no perceptual distortions. Other psychedelics, like LSD and psilocybin, are also effective, but they have to be taken orally and so they work on a scale of 30+ minutes.

This post is about the condition, using psychedelics to treat it, and ClusterFree — a new [...]

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Outline:

(01:49) Cluster headaches are really fucking bad

(03:07) Two quotes by patients (from Rossi et al, 2018)

(04:40) The problem with measuring pain

(06:20) The McGill Pain Questionnaire

(07:39) The 0-10 Numeric Rating Scale

(09:14) The heavy tails of pain (and pleasure)

(10:58) An intuition for Weber's law for pain

(13:04) Why adequately quantifying pain matters

(15:06) Treating cluster headaches

(16:04) Psychedelics are the most effective treatment

(18:51) Why psychedelics help with cluster headaches

(22:39) ClusterFree

(25:03) You can help solve this medico-legal crisis

(25:18) Sign a global letter

(26:11) Donate

(27:06) Hell must be destroyed

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First published:
February 7th, 2026

Source:
https://www.lesswrong.com/posts/dnJauoyRTWXgN9wxb/near-instantly-aborting-the-worst-pain-imaginable-with

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Narrated by TYPE III AUDIO.

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