A study demonstrates the safety of the hallucinogen psilocybin to treat anorexia nervosa

Anorexia nervosa lacks a pharmacological approach capable of reversing the main symptoms. As this eating disorder is increasing, new treatments are urgently needed to improve clinical outcomes.. In adolescents, the incidence is 1%, many patients, mostly female, reach adulthood with the disease without curing.. In adults, it is 0.6%. And it is part of the complex pathologies that are included in eating disorders (TCA).

In a new study, published in Nature Medicine, involving 10 adult women whose body mass index was very low (less than 19) and met the criteria of the Diagnostic and Statistical Manual of Mental Disorders, the safety of synthetic psilocybin is demonstrated to treat anorexia nervosa.. The study was led by the team of Stephanie Knatz Peck, at the Center for Eating Disorders at the University of California San Diego (UCSD)..

Participants received a single 25mg dose of synthetic psilocybin combined with psychological support. The primary objective was to assess safety, tolerability, and feasibility after treatment using the incidence and occurrence of adverse events and clinically significant changes in electrocardiogram, laboratory tests, vital signs, and suicidality..

“The treatments available to us have limited efficacy, so I look forward to any news about new approaches,” says Joaquim Raduà, psychiatrist and head of the IDIBAPS Image of Disorders Related to Mood and Anxiety research group, in statements to SMC. But he qualifies that the work “is very initial, very small, without a control group, and basically he just wanted to know if psilocybin is a safe and tolerable treatment”.

This is also affected by Carmen Moreno, from the Institute of Psychiatry and Mental Health of the Gregorio Marañón Hospital. “The important thing is safety after using a single dose”. As he details this medium, “measuring tolerability in a time space of up to three months is important”.

No clinically significant changes in electrocardiogram, vital signs, or suicidality were observed.. Two participants developed hypoglycemia unawareness after treatment, which resolved within 24h.. There were also no other clinically significant changes in laboratory values.. All side effects were mild and transient in nature..

The qualitative perceptions of the participants suggest that the treatment was acceptable to the majority of the participants.. “The clinical impression is that the treatment has been good for them, not against anorexia itself, since it only serves to measure the feasibility of the study,” says Moreno, who stresses that from this work “it is not feasible to measure the efficacy, because there is no control group. They all knew they were taking it. It must be taken into account that with these drugs there is a certain tendency to autosuggestion in operation, so this factor must be taken into account”.

Why do experts question this study?

Raduà also points out that the fact that four patients have been observed to improve is not significant because “we do not know if it was due to psilocybin, psychological support or simply by chance. For this reason, we should avoid placing too much hope until there are larger, controlled studies.”.

On this, Alberto Ortiz Lobo, a psychiatrist at the Carlos III Day Hospital-La Paz University Hospital in Madrid, explains that “the profound placebo effect that the hours of medical supervision and professional care associated with psychedelic treatment are likely to produce is overlooked.”. As SMC collects, Ortiz Lobo criticizes the work because “this study is representative of this fashion and has very important limitations. It starts from an unproven hypothesis: that serotonergic function is altered in people diagnosed with anorexia nervosa and that psilocybin may be effective because it acts specifically on this neurotransmission system”

The Carlos III Day Hospital expert adds that the research “is of a very low quality, with a minimal sample”, and that, like most of the work being done with psychedelics, “does not pay attention to the way in which the immediate psychoactive effects of drugs impact people's feelings and behavior”..

The results collected by the US researchers point to the safety of psilocybin therapy, tolerable and acceptable for female anorexia nervosa, which is a promising finding given the physiological dangers and problems related to treatment.. The Gregorio Marañón psychiatrist emphasizes that “these drugs can trigger side effects and are not the panacea for all psychiatric problems that have no other therapeutic options. We have to measure how we will use them.”.

It should be noted that Knatz Peck points out in the publication that “more research is needed based on the assumptions we have reached”. The co-investigator and lead therapist is participating in other trials evaluating psilocybin treatment for anorexia nervosa and looking to take the next step to this proof of concept.

Door open to the use of hallucinogens in psychiatry

This is not the first study to test the use of psilocybin in a psychiatric disorder. Moreno recalls that there is already more advanced research in the area of depression. “For a few years now it has been used in an organized way, there have been publications that demonstrate its usefulness”. And he points out that “always together with a support therapy”.

For his part, Ortiz does not hesitate to point out that “as with other psychopharmacological treatments, psilocybin and the rest of the psychedelics are becoming popular through the powerful combination of financial interests and the despair that mental suffering causes in people who suffer from it.. However, its generalized clinical utility has not been proven and this study does not provide any news in this regard, except to further contribute to the dissemination of these substances.”.