Alfredo Parra 🔸

Karma: 1,843

I’m the Director and Co-Founder of ClusterFree, an advocacy and research initiative focused on cluster headaches. ClusterFree was incubated by the Qualia Research Institute.

I previously worked as Chief of Staff at the Institute for Law & AI (formerly “Legal Priorities Project”) and as COO at the Center on Long-Term Risk (formerly “Effective Altruism Foundation”). I also co-founded EA Munich in 2015. I have a master’s and a PhD in Computational Science from TU Munich and a bachelor’s in Engineering Physics from Tec de Monterrey.

I also have a blog called Globally Bound where I write about consciousness and extreme suffering. (You can encourage me to write more by donating here.)

🔶 10% pledger since 2015

Alfredo Parra 🔸 16 Jun 2026 8:05 UTC
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on: Emerging evidence on treating cluster headaches with DMT
Relevant abstract just published in Neurology: DMT use in Cluster Headache: Interim Analysis of an International Survey (S23.003)
From a total 248 completed surveys, 100 participants met criteria for cluster headache. Of these, 84% were male and average age was 49 years. The most common place to have learned about DMT treatment was social media/online. More than one mode of ingestion was often tried, but 75% had used a vape pen. Among those who used DMT to abort attacks (n = 85), the majority reported it completely eliminates pain (67.5%) and that it works every (45.7%) or almost every (35.8%) single time. Over half reported that DMT worked in under 30 seconds, and all participants reported either no change or an improvement in their health with DMT use.

Alfredo Parra 🔸 25 May 2026 17:19 UTC
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in reply to: Arepo’s comment on: My Current Solution to the Repugnant Conclusion
Thanks! Upvoted because I agree that we should consider EI/OI in population ethics, but disagree with the conclusion, which depends on the specifics of how you aggregate the pinpricks. Without going into too much detail, an analogy here is that if you have two soap bubbles and you bring them closer together until they touch, they can merge into a bigger bubble, possibly with emergent properties that go beyond those of the two individual bubbles. It’s a new kind of thing, well defined through topology, and having little to no resemblance to the two-separate-small-bubbles system.
Will publish more on this topic soon!

Alfredo Parra 🔸 3 May 2026 6:51 UTC
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on: Notes on equanimity from the inside
Thanks for sharing! I think you might enjoy in this conversation with Roger Thisdell about classical enlightenment and valence structuralism, which touches on some of the points you raise. (You probably also saw Scott Alexander’s In What Sense Is Life Suffering?)
Deep down consequentialism is a judgmental philosophy that evaluates world states as better or worse.
It’s going to be interesting to see how the field of ethics (esp. population ethics) evolves as philosophers take phenomenology more seriously (in particular exotic states, many of which Buddhists have explored and described in excruciating detail for centuries), not to mention things like open individualism or mixed valence.

Alfredo Parra 🔸 22 Apr 2026 17:27 UTC
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in reply to: Derek Shiller’s comment on: Discussions of (p)sentience of small animals miss the point
In case it helps, this is (super roughly!) how I think about some of these questions:
- I think panpsychism fares much better than functionalism (generally). It seems odd to me that (many) (computational) functionalists seem OK with claims like “consciousness is simply what certain algorithms / information processing / etc. feel like from the inside” (especially given the arbritrariness of algorithms), yet struggle to see how consciousness could be what the fundamental fields of physics (or whatever is at the base layer of reality) feel like from the inside (those are not arbitrary).
  - More precisely, phenomenally bound minds like ours are what certain configurations of the fields of physics, and especially the EM field, feel like from the inside.
  - Though as Atai Barkai has very eloquently pointed out, simply stating that the fields of physics are made of qualia (~Russellian monism) does not automatically solve the phenomenal binding problem. But that’s a separate (IMO surmountable) problem (and Barkai gives one possible solution).
- I currently think that the Symmetry Theory of Valence, despite being in its infancy, has more explanatory power and is more parsimonious than competing theories of pleasure and suffering.
- Putting panpsychism and STV together paints this (admittedly hand-wavy) picture:
  - Any physical system has an associated valence, proportional to its degree of symmetry/asymmetry (consonance/dissonance).
    In the case of human nervous systems, this could be the degree of dissonance present in the spectrum of EM waves that make up our world simulation; see here for more.
  - Evolution made use of this low-level fact about the universe to design organisms that feel pleasure when they do things aligned with their reproductive success (and the converse with suffering).
    But this is an imperfect implementation that can be gamed. For example, we can feel lots of pleasure for reasons totally unrelated to our reproductive success (e.g. the jhanas or a good 5-MeO-DMT trip, which STV seems to predict / capture just fine: the phenomenal fields become simpler and more harmonious).
(Not surprisingly, this position is very QRI-informed.)

Alfredo Parra 🔸 22 Apr 2026 12:59 UTC
2 points
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on: Epistemic interventions are a promising way to reduce power concentration
(I started reading this post hoping to learn what exactly an epistemic intervention is, and I stopped reading when I realized it wasn’t going to be defined / the reader should be familiar with the term. I guess I’m not the target audience but I thought I’d share. :))

Alfredo Parra 🔸 21 Apr 2026 13:52 UTC
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on: Discussions of (p)sentience of small animals miss the point
This exact point has been on my mind for some time, so thanks for writing this!

Alfredo Parra 🔸 15 Apr 2026 14:48 UTC
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in reply to: Vasco Grilo🔸’s comment on: Abandoning functionalism: Some intuition pumps
Thank you, glad you liked it!

Alfredo Parra 🔸 8 Apr 2026 14:10 UTC
17 points
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in reply to: SiobhanBall’s comment on: Alfredo Parra ’s Quick takes
I am! Announcing ClusterFree: A cluster headache advocacy and research initiative (and how you can help)

Alfredo Parra 🔸 8 Apr 2026 8:57 UTC
27 points
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on: Alfredo Parra ’s Quick takes
Some women on the Facebook support group “Cluster Headache Patients” comparing labor pain to cluster headache pain:
- “Honestly, I had a natural childbirth and a cesarean and cluster headaches are 10 times worse than both.”
- “2 unmedicated births for me. Would rather do that every day than have another cluster”
  - “every day though, really?”
  - “yes. I’d rather go through childbirth without pain relief than CH.”
- “tenfold worse than popping a baby out”
- “Nah, labour/giving birth is a walk in the park compared to ch […] I was in labour with my son for nearly 3 days, then the midwife had to break my cervix with her hands, but I’d still rather do that again than have another CH”
- “Labor pain doesn’t even come close to CH! I’d choose labor pain ANY day over suffering from another CH”
- “CH is a million times worse”
- “I had 4 children, 3 were natural. CH is worse.”
- “I’d rather have a baby. And my placenta tore during all natural childbirth.”
- “I gave birth to 4 different babies. The smallest being 8lbs 14oz. The biggest being 10lbs 15oz. I would much rather give natural birth all over again than a CH.”
- “I’ve had three babies—one was overdue and born with his arm over his head. Having a baby is still cake compared to clusters.”
These are just a few. They go on and on. (So far only one woman claiming childbirth was worse, who “nearly bled out in childbirth, got an episiotomy with zero freezing/drugs.”)

Alfredo Parra 🔸 24 Feb 2026 18:56 UTC
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in reply to: Vasco Grilo🔸’s comment on: All pains are comparable?
Nice response, thanks a lot! :) I might share some more thoughts soon (e.g., maybe the assumption that pain is a one-dimensional quantity could be doing some additional heavy lifting here; and I guess others have discussed problems with aggregationism, which may still apply even if all pains are comparable in the sense that you mean).

Alfredo Parra 🔸 23 Feb 2026 18:01 UTC
7 points
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on: All pains are comparable?
Thanks for writing this, Vasco! And thanks for inviting me to comment given that you expected me to disagree with the conclusion (which I do :)). I’m still confused about these questions but I think there are two analogies from physics/mathematics that might apply here and cast doubt on the post’s conclusions, namely, (1) phase transitions and (2) topological transformations.
NB: I recorded a voice note into Claude and then asked it to structure and clarify my thinking, which I then cleaned up.
Your argument, as I understand it, goes something like this:
1. A human body can be described by the state of all its fundamental particles.
2. For any two states that differ only infinitesimally, the pain intensities must be quantitatively comparable.
3. You can get from any state to any other state via a chain of infinitesimal changes.
4. Therefore, all pain intensities are quantitatively comparable.
I think (2) is doing a lot of heavy lifting here, and I don’t think it’s obviously true. The key issue is that continuous variation in underlying physical parameters does not entail continuous variation in the properties that emerge from them. This happens for example in phase transitions and topology.
Phase transitions
When you heat a ferromagnet continuously, nothing dramatic happens for a while. Then, at a specific critical temperature (the Curie temperature), ferromagnetism doesn’t just decrease, but it vanishes entirely. The property “being able to attract iron” is not something that fades smoothly to zero. It disappears at a sharp threshold, even though the underlying control parameter (temperature) was varied continuously.
Similarly, when you cool certain materials, electrical resistance drops to exactly zero at a critical temperature (superconductivity). “Very low resistance” and “zero resistance” are not just quantitatively different. Superconductors exhibit qualitatively new phenomena (persistent currents, the Meissner effect, flux quantization) that materials with merely very low resistance simply do not have.
In our earlier exchange, I used the water/steam analogy, and you responded that we can still compare the temperature of water and steam. That’s true, but I should have added that I think pain might not be analogous to temperature, but to some other property. Temperature is a property that varies smoothly across the phase boundary, but there are other properties that only exist in one phase. For example, steam can do mechanical work via expansion (it drives turbines); liquid water cannot. Liquid water has surface tension (it forms droplets, menisci, capillary action); steam doesn’t. These properties aren’t “less” or “more” across the transition. They’re categorically present or absent.
So the question is: is pain intensity more like temperature (a quantity that varies smoothly across all physical states), or more like magnetism or surface tension (a property that can appear, disappear, or transform categorically / jump at critical thresholds)?
I think there’s good reason to suspect the latter. For example, neurons themselves exhibit all-or-nothing action potentials. Below a voltage threshold, nothing propagates. Above it, a full spike fires. Continuous variation in input produces a binary output. If certain pain experiences depend on whether particular neural cascades fire or not, then the inference from “infinitesimal change in particle positions” to “infinitesimal change in pain intensity” breaks down at these thresholds.
Topological transformations
Consider a rubber sphere. You can stretch it, compress it, bend it, twist it however you like, and it remains topologically a sphere. But to turn it into a torus (a donut shape), you need to introduce a hole. The number of holes (the “genus”) is an integer. It cannot change by 0.01. And yet this discrete invariant determines fundamental properties of the surface, like how many independent loops can exist on it.
Or consider a loop of string. You can deform it continuously all day long, but the moment a crossing is introduced and locked in, you get a knot, which is a topologically distinct object. The unknot and the trefoil knot are categorically different. You cannot “halfway” have a knot. Knot invariants are discrete, even though every local manipulation of the string is smooth.
Suppose the morally relevant feature of a conscious experience is something like a topological property of the neural dynamics: perhaps the structure of information integration, the geometry of recurrent loops, or the topology of attractors in the brain’s state space. More concretely, if pain was, say, the degree of dissonance in the electromagnetic waves generated by the nervous system, then introducing a topological defect into the field could suddenly allow new levels of dissonance not possible without the defect.
If that’s the case, then the argument “moving an electron by 10^-100 m cannot prevent the pains from being quantitatively comparable” would be analogous to arguing “stretching a rubber sphere by 10^-100 m cannot change its genus.” For most configurations, that’s true. But at a critical configuration, that tiny stretch is exactly what punctures the sphere and changes the genus from 0 to 1. The transition is sharp and local in parameter space.
So overall, I think the burden of proof is on showing that pain intensity actually behaves like temperature (smoothly varying, phase-invariant) rather than like magnetism, surface tension, or genus (categorically structured, with critical thresholds). I think it’s more likely to be the latter (and that the symmetry theory of valence will be key in finding the solution).
My intuition is that the conclusion “I would prefer warming up slightly cold patches of soil for sufficiently many nematodes over averting 1 trillion human-years of extreme torture” should be a reductio ad absurdum for the argument, and maybe the two angles above show how one might escape such a conclusion.
I hope this helps clarify where I’m at!
What links here?
- Cause prio cruxes in 2026? by Hayley Clatterbuck (11 Nov 2025 15:22 UTC; 83 points)

Alfredo Parra 🔸 18 Feb 2026 9:41 UTC
3 points
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in reply to: Nicolas Mace’s comment on: Quantifying the Global Burden of Extreme Pain from Cluster Headaches
Indeed, I updated some model parameters for the simulations in the paper, which resulted in a lower DLES burden calculation. I believe the main difference was the estimated fraction of severe attacks relative to milder attacks.
Given the large error bars, I also included a sensitivity analysis in the paper, i.e., I calculated the DLES burden assuming lower and upper bounds for various key variables. This resulted in lower and upper bounds of 700k and 11m DLES.

Alfredo Parra 🔸 16 Feb 2026 20:28 UTC
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on: Introducing our newest charity recommendations—from mobile contraceptive clinics to digital mental health care
addressing large, persistent gaps in care or prevention that lead to avoidable suffering or poor life outcomes
I’m so grateful you’re looking into this! I think there’s a lot of low-hanging fruit in this space (I’ll soon share other ideas I have for folks to look into). I’ll be following with excitement. :)

Alfredo Parra 🔸 8 Jan 2026 14:21 UTC
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in reply to: VeryJerry’s comment on: Emerging evidence on treating cluster headaches with DMT
Thanks for all this info! Keep it coming; I’m keeping track and plan to make good use of it. Get in touch if you’d like to discuss more. :)

Alfredo Parra 🔸 28 Dec 2025 19:29 UTC
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on: Launching the India Animal Welfare Funding Circle
Wishing you all the best! :)

Alfredo Parra 🔸 28 Dec 2025 19:28 UTC
3 points
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in reply to: NickLaing’s comment on: The Best Treatment for the Most Painful Medical Condition Is Illegal
Thanks for sharing your thoughts! While I’m obviously sad that you’ve updated negatively, this exchange has been very helpful for me to reflect on how to communicate my level of confidence in these treatments, especially given the little data we have from RCTs specifically. The total evidence still looks overall highly compelling to me (I wouldn’t be working on this ~full time otherwise), but I’ll work on improving my communication (and generating more scientific evidence).
The main thing I’d like to say is that I’m really not committed to psychedelics as an intervention (since you brought up the lobbyist language), and I’m particularly excited and hopeful about non-hallucinogenic analogues (such as BOL-148 and Conjugated Psilocin), as well as about non-pharmaceutical interventions, which we’re also exploring. Ultimately, I just want patients to have universal access to treatments that safely and effectively prevent or abort their attacks. Currently, I sincerely believe those happen to be indoleamines.
If the effect is really as strong as claimed, you wouldn’t even need 100 patients for an RCT. Perhaps clusterfree could even make this happen faster
Absolutely agree, and we’re actively thinking about how to do this!

Alfredo Parra 🔸 20 Dec 2025 13:21 UTC
3 points
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on: Where did you donate this year?
Clusterbusters, because torturous pain belongs to the past (especially if it can be easily prevented).

Alfredo Parra 🔸 20 Dec 2025 12:49 UTC
9 points
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in reply to: Henry Howard🔸’s comment on: The Best Treatment for the Most Painful Medical Condition Is Illegal
I understand it seems hard to believe! And yes, I’m motivated to support / advocate for RCTs and I’m developing various ideas with some collaborators (not just involving psychedelics). I agree that more data published in peer-reviewed journals is very much needed.
I still genuinely believe that the funding and legal barriers are very difficult to overcome (plus other barriers). A good resource on this topic is the book Psychedelic Outlaws (describing the history of psychedelic use and research for CH). This deep research by Claude may also provide useful context: Why psychedelic research for cluster headaches has stalled despite decades of patient evidence. It concludes:
The documented barriers to psychedelic cluster headache research reveal systemic failures across every institution that might otherwise advance treatment. Schedule I classification adds years to research timelines. NIH has invested almost nothing in cluster headache specifically. Pharmaceutical companies see no return in treatments requiring only three doses annually. Academic institutions impose unique scrutiny on psychedelic protocols. Patient recruitment struggles with rarity, episodic presentation, and placebo reluctance.
The BOL-148 story crystallizes the tragedy: a non-hallucinogenic compound showed unprecedented efficacy in 2010, yet required 13 years to enter Phase 1 trials because it fell between orphan drug and commercial viability. As Bob Wold observed: “You can’t introduce transformative medicine into a broken healthcare system.” The gap between patient discovery in 1998 and the current state of research—with perhaps one dedicated US researcher and trials measured in dozens of participants—represents what Halpern called “a process that has begun 40 years too late.”

Alfredo Parra 🔸 20 Dec 2025 8:02 UTC
5 points
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in reply to: Henry Howard🔸’s comment on: The Best Treatment for the Most Painful Medical Condition Is Illegal
Why suspicious? The fact that DMT aborts cluster headaches is a pretty recent discovery. The word is just beginning to spread among sufferers. And there are very few researchers working on this topic, and very little funding generally, and it can be pretty difficult to get all the permissions needed to run trials using psychedelics. (I wouldn’t be surprised if Schindler’s group at Yale was running the DMT survey as a preliminary step to justify running a proper trial. Note that Schindler “is believed to be the only researcher in the United States studying psychedelics in headache disorders.”)

Alfredo Parra 🔸 18 Dec 2025 14:27 UTC
10 points
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in reply to: Henry Howard🔸’s comment on: The Best Treatment for the Most Painful Medical Condition Is Illegal
Thanks for your comment!
It is true that published studies on psychedelics are few and small. Hopefully that will change but, currently, investment into cluster headache is minute relative to its severity and prevalence.
There are no studies on DMT in particular (though one survey is being carried out at Yale). However, we’ve argued that the little evidence we have on DMT specifically should be taken very seriously (which is what motivates the Yale group).
In medicine you quickly learn that anectode is extremely unreliable and the average person is positively busting to attribute cause and effect to whatever they just experienced. Every homeopathic remedy/energy healer/prayer/crystal/snake oil has its die-hards who will give you convincing anectodes of immediate success, so doctors become rightly extremely skeptical about these stories.
I think this definitely does not apply to DMT for CH. As mentioned in the post I linked above, patients can report going from experiencing the worst possible pain to being completely pain free within seconds of inhaling DMT. The cause and effect could not be any clearer. (There are also other statistical ways to quantify the reliability of anecdotes, see e.g. here.)
The actual evidence he provides is this review of some case studies and surveys and 4 clinical trials but which have pretty low numbers. The review itself says: “The small number of participants in each study limits reliability and generalizability of the findings. Even with ongoing work, differences in dosing regimens and outcomes among studies will limit the consolidation of findings”
(And yet it’s worth pointing out that two of the three co-authors of that review, namely Christopher Gottschalk and Emmanuelle Schindler, are among the strongest supporters of psychedelic treatments for CH. Gottschalk is the Director of Headache Medicine at Yale and immediate past president at the Alliance for Headache Disorders Advocacy.)
Combined with the small risk of psychosis from psilocybin I understand why health systems wouldn’t want to rush into mainstreaming them as treatment.
How big is the risk of psychosis at low doses, and how does it compare to experiencing literally the worst possible pain, day in and day out?
I’ve been thinking about / working on cluster headaches since summer 2024, not just reading the academic literature but also following support groups online and talking to patients directly. There’s no doubt in my mind that psychedelics help many patients enormously, and at low doses for most patients. I know some patients who decide not to take psychedelics, but we should give those who do want to use them the right to try them without any legal repercussions.

Alfredo Parra 🔸

Phase transitions

Topological transformations