Twice a month, our friends from Blossom will update you on the latest in psychedelic research. Enjoy an in-depth look at major studies and updates on recent psychedelic publications.
This type of ketamine may be the next big psychedelic
Ketamine has consistently been making headlines over the last two decades as a treatment for depression.
Though the effects may not last as long as other psychedelics, ketamine is widely available as a medicine. One specific form of ketamine, esketamine, has been approved for treatment-resistant depression and is marketed by Janssen Pharmaceuticals (Johnson & Johnson) as Spravato. But, you barely ever hear about another type of ketamine, arketamine.
Arketamine (R-ketamine) and esketamine (S-ketamine) are the two ‘mirror’ images (enantiomers) of ketamine. Just like your hands are near-identical, these two enantiomers are the left- and right-handed versions of ketamine. Ketamine is the combination of both compounds.
Many psychedelics are just known as the complete compound. MDMA, for instance, combines the left and right hands. How these molecules interact with the body is slightly different, but for MDMA and many others, the individual handedness hasn’t gotten much attention.
The latest publication on arketamine hopes to bring a change to this status quo. Ji-Chun Zhang and colleagues dive into the literature on esketamine. They find surprisingly positive results for ketamine.
Arketamine, better than ketamine?
What immediately stands out is that arketamine, at the same dose, produces fewer adverse psychological effects such as depersonalization and hallucinations. In fact, one study reviewed showed that participants in the arketamine part of the trial only experienced “a state of relaxation.”
The lower incidence of psychological effects has been known since before the turn of the century. Esketamine was chosen as the preferred handedness, not because of the side effects but because researchers at Johnson & Johnson thought that the inhibition of NMDAR (a receptor in the brain) was crucial for the anti-depressant effect. Esketamine, not arketamine, has a higher affinity for this receptor.
Researchers nowadays question this reasoning. Studies in mice consistently show that arketamine has a similar, if not better, effect on depression. Only in 2020, two decades after the first ketamine for depression studies, was this confirmed in a small trial in humans.
Following up on this study, trials of arketamine are underway. Perception Neuroscience (part of the atai family of companies), Otsuka, and two Chinese companies lead the charge. In the coming two years, results will show if the initial findings hold up under scrutiny. If the trials report positive findings, arketamine may one day dethrone ketamine as a rapid-acting antidepressant.
More psychedelic research news…
Cancer risk from psychedelics unfounded
An urban myth started in the late 60s said that LSD scrambles your molecules and increases cancer risk. Known to be nothing more than fearmongering, the hypothesis had never really been put to the test.
An analysis of data from over 200.000 people finds no association between psychedelics use and the risk of cancer or leukaemia (hematologic cancer). Yet another urban myth that we can safely retire.
The enormous gulf between recreational and medical psychedelic use
As much as everyone wants psychedelics to become medicines, recreational users barely discuss their use with their primary caregivers. A survey of psychonauts finds that 75% never discuss their use, and all but some (3%) had never done psychedelics in a medical setting. Four out of five would be willing to do psychedelics as therapeutics if legally available.
Mice that received psilocybin didn’t decrease their food intake
Human trials have shown excellent results in treating eating disorders (specifically anorexia nervosa) with psychedelics. Patients had a better relationship with food and showed remarkable improvements.
The long-standing discussion is if it’s just changes in the brain chemistry or whether an analysis at the psychological level is more appropriate. A study in mice showed that psilocybin did not affect the eating behaviour of mice. Though difficult to translate to humans, this is one vote in the direction that psychological effects do indeed play a pivotal role in the effects of psychedelics.