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Want to Help Test a New Solution for Phantom Limb Pain?

Jul 20, 2023 |

Reprinted with permission from Amplitude Magazine

If you experience phantom limb pain and want to help evaluate a possible treatment, the University of California at San Diego’s Psychedelic Health and Research Initiative (PHRI) is actively recruiting participants for a groundbreaking research project.

PHRI has launched a $1.3 million study to test the safety and effectiveness of psilocybin—the active ingredient in hallucinogenic mushrooms—in treating PLP. It’s the first study to rigorously, scientifically assess psilocybin’s potential to mitigate PLP, and it belongs to the growing wave of serious research that’s focused on psychedelic medicine’s benefits in alleviating chronic pain, depression, post-traumatic stress, and other conditions that routinely affect amputees.

As you might recall, we explored this emerging science a few issues ago, with emphasis on the powerful anecdotal evidence that psilocybin can alleviate PLP. Here’s your chance to contribute directly to the accumulation of knowledge and the discovery of solutions. And as a bonus, you get paid $600 for taking part.

We’ve provided some details about the project below. If you think you’re a good candidate and want to learn more, contact the PHRI at (619) 432-5278 or at You can also scan the adjacent QR code to jump directly to the project’s pre-intake survey.

What will participants be asked to do?

That depends on whether you take part in Phase 1 or Phase 2 of the study. PHRI is recruiting for both phases. Here’s the basic outline.

In Phase 1, participants will be provided with either a therapeutic dose of psilocybin or a placebo (chosen at random). All participants will provide feedback about their experience the next day, and then take part in followup surveys for a few weeks to monitor the status of their PLP, mood, anxiety/trauma levels, and other indicators. You’ll also have MRI brain scans before and after your dose, enabling researchers to see if any changes in brain activity take place downstream of the session.

Phase 2 involves a larger commitment. There are two doses instead of one, and the post-dosing followup period extends for roughly a year, with periodic surveys to chart the long-range trajectory of your PLP and overall emotional health. Before-and-after MRIs are part of Phase 2 as well.

I’ve never taken psychedelics before. How do I know I’ll have a safe experience?

“There’s almost no better scenario in which you could have this type of experience,” says Fadel Zeidan, the project’s principal investigator and an associate professor of anesthesiology at UCSD. Multiple layers of precaution are in place, beginning with an initial screening to ensure that candidates are healthy enough (both physically and psychologically) to participate. After clearing the screening, you’ll move on to preparatory sessions the day before your dose to establish a rapport with the clinical team, get a roadmap of what to expect, and seek answers to any questions or concerns.

“We spend a lot of time beforehand allowing participants to develop rapport with the clinical team, because you don’t want to be in this potentially vulnerable state with strangers,” says Ethan Hurwitz, another key member of the research team. “You want to be with people who you trust and who have points of reference to provide any support you might need. We spend a lot of time developing trust and rapport with the monitors beforehand, and training the participants about how to navigate the space they’re going to be in.”

“Safety is our number one priority,” Zeidan adds. “So “We have gone through this with many patients, and we have not had any adverse events. This is a very sacred space, and we certainly don’t want to be the ones to mess it up.”

What’s the dosing session like?

Dosing sessions themselves take place in a closely controlled environment. “It’s a full-blown medical research clinic,” Zeidan says, “even though it’s decorated kind of like the parking lot of a Grateful Dead concert.” Each session is overseen by specialized monitors who are hand-picked for their training and experience in working with psychedelic medicines. Doctors and nurses are very close at hand, along with “rescue medications” that can be administered should the subject wish to halt the experience. As the psilocybin takes effect, participants are encouraged to focus their consciousness inward. “Participants are laying on a couch with eyeshades and headphones on, and we really encourage them to go into the experience,” Hurwitz says. “It’s a very different context than if you’re at Burning Man or out in the forest or something.”

The psychedelic effects last about five or six hours. Monitors will check vital signs periodically, but otherwise subjects can have as little (or as much) interaction with the clinical team as desired. Immediately afterward, participants will begin to describe their experience and unpack their emotions. That process will continue the following day in formal integration sessions with the clinical team.

What’s the mechanism by which psilocybin relieves PLP? How does it affect the brain?

Nobody really knows, which is one reason this is such an important research project. The brain MRIs in this study may go a long way toward suggesting an answer; as the first before-and-after brain images ever produced in this context, they have the potential to yield new insights about psilocybin’s effects on neurological structure and activity, and how those correlate to particular symptoms.

But qualitative and observational data are also a big part of the picture, says Jon Dean, a post-doctoral fellow at UCSD who specializes in psychedelic-induced pain relief. “It doesn’t really make sense that these people experience pain in a limb that isn’t there,” Dean says. “That suggests that there’s something centrally mediated, something related to the trauma of the amputation, even if it’s a planned amputation. We think the medicine is interacting with the individual’s ego to fix the aberrant signals that are going to this area. What we deduce from the small pilots we’ve run is that people are really going back through their trauma, with the aid of the medicine and the therapists, to come out with a new relationship to that experience.”

Another theory that’s picking up steam lately involves neuroplasticity, Hurwitz says. “The idea there is that while you’re experiencing the effects of the medicine, there’s a lot more functional connectivity and crosstalk between different brain areas, and those new interconnections allow people to reprocess their experiences in new ways.” It’s important not to overinterpret these ideas, Hurwitz adds, because the field is still so new.

Who’s eligible to participate?

The researchers are seeking amputees, age 18 to 75, who suffer from chronic phantom limb pain that hasn’t responded well to other treatments. You can live anywhere in the country, but you’ll need to travel to San Diego for the actual dosing session and MRI scans. To get more information and/or declare your interest in enrolling, contact the PHRI at (619) 432-5278 or at