
“Psychedelic medicine” or even “psychedelic therapy”: these are becoming more and more popular in the media. Patent evidence of renewed psychiatric interest in these molecules. Over the past twenty years, we have seen experiments on modest cohorts of patients suffering from severe depression, post-traumatic stress, or even addictions that are difficult to treat with conventional medications. This research changes the sulfuric image of these substances. By “retreating” them, the taboo seems to be gradually lifted…
What are psychedelics?
The term “psychedelic” was coined by the English psychiatrist Humphrey Osmond in 1956 in correspondence with the writer Aldous Huxley. These substances include synthetic products such as the famous LSD or ecstasy, and natural compounds from plants or mushrooms:
- ketamine
- LSD or lysergic acid diethylamide
- MDMA is also called ecstasy.
- psilocybin mushrooms,
- ayahuasca, a vegetable decoction from Amazonian plants containing dimethyltryptamine (DMT)
- ibogaine, a substance derived from the African iboga tree.
- mescaline, an alkaloid derived from peyote, a cactus native to northern Mexico.
Their reception causes visual and auditory hallucinations and an altered state of consciousness. Perception, feelings and thoughts are greatly altered. It is difficult to predict the effects obtained from one patient to another. Another discovery reported by researchers and clinicians is the absence or weakness of the addictive effect of some of these molecules (MDMA and ketamine do not fall into this category), in contrast to other drug classes such as opioids, or substances such as alcohol and nicotine.
All of these substances have been banned and considered illegal in France since 1966, and the country was one of the first to ban them. A few years later, they were blacklisted around the world when the UN placed them on its list of dangerous drugs and required highly controlled therapeutic use.
These psychotropics, however, quickly entered Western pharmacopoeias as soon as they were “discovered” by Europeans and North Americans in the 19th century. They were studied and tested by researchers, clinicians and therapists in the 1940s and 1950s.
A decade later, the picture is changing dramatically. These substances are considered dangerous by US authorities and a large part of its public opinion. The country is at the epicenter of the Vietnam War, a conflict in which its youth are actively involved. These social movements worry conservative America. The government and part of the media then targeted the beatnik counterculture, which emphasized the use of psychotropic drugs and into which the protesting youth were immersed.
How do they act on the brain?
The mechanisms of operation are not yet fully understood. Research has stopped for several decades, and we still know relatively little about their mode of action. According to the typology proposed by the synthesis of the use of psychedelics in psychiatry, three pharmacological profiles emerge according to their action on the type of receptor in the central system:
- serotonergic psychedelics (LSD, psilocybin, DMT, mescaline)
- empathogens (MDMA)
- dissociatives (ketamine).
- ibogaine is more difficult to classify: a substance that is metabolized in the body, noribogaine acts simultaneously on several categories of receptors.
The penetration of molecules such as LSD or psilocybin into the brain seems to lead to hyperconnection between neurons. These neural networks usually do not interact with each other. Patients of Robin Carhart-Harris, director of the Imperial Center for Psychedelic Research at Imperial College London, interviewed by Science et Avenir in 2019, used computer metaphors to describe what they felt: “Feelings of ‘rebooting’ or rebooting the brain, or ‘defragmenting’.” This increase in “brain plasticity” would allow the nerve cells of people suffering from major depression to be reprogrammed, and would free patients suffering from post-traumatic stress, alcohol or drug addiction from their obsessive loop.
Why are we talking about psychedelics again?
Psychiatry believes that treatments for certain depressions, addictions, and addictions, even backed up by psychotherapy, are ineffective. Since the 2000s, psychedelics have been seen as promising psychotherapeutic agents by some researchers. Ketamine, LSD, and psilocybin are once again gaining the attention of the psychiatric community.
The change in perception and consciousness induced by psychedelics may have a positive effect on treatment-resistant patients. But be careful! There are not enough large-scale clinical trials and double-blind trials to test and confirm these hunches.
Researcher interest and funding is back at the meeting, materialized by the birth of Psychedelic Medicine, the first peer-reviewed scientific journal entirely dedicated to this resurgent field of research, in the fall of 2022. To dispassionately argue about these substances and move forward… by the scientific method.
The Australian Medicines Agency announces permission from July 2023 to prescribe MDMA and psilocybin to psychiatrists and under very strict conditions for patients suffering from post-traumatic stress and acute depression.