Psychedelics in the treatment of anorexia – a new pilot study

Anorexia nervosa is a serious psychiatric disorder for which there are limited treatment options, and it has one of the highest mortality rates of any psychiatric diagnosis. A pilot study is now underway at Lund University in Sweden, where researchers are investigating whether psychedelic drugs have an effect on young patients with the disorder.

Ward Five at the adult psychiatric clinic in Lund is fully adapted for patients with anorexia nervosa. Participants for the new study will be recruited from here and elsewhere within Region Skåne (the regional government with responsibility for healthcare). The pilot study, which has recently received approval from the Swedish Medical Products Agency and the Swedish Ethical Review Authority, will start in the autumn and involve 40 patients aged between 16 and 35. The study is the first in the world to systematically investigate psilocybin treatment for young anorexia patients.

“Anorexia has a hereditary component and is also more common in people with autism or obsessive-compulsive disorder. “Anorexia typically has two peak ages of onset, occurring first at about 14 and the the second around 18. That is why we wanted to include patients from the age of 16 and up who had relapsed at least once, obviously with parental consent in the case of minors,” says Pouya Movahed Rad, associate professor and head of the research group  at Lund University, and consultant psychiatrist at Psychiatry Skåne.

The study is primarily a clinical safety study, in which researchers will systematically evaluate the risks and side effects of psilocybin compared with conventional treatment for anorexia nervosa. They will also examine time to relapse, changes in BMI, mental well-being, and potential alterations in communication between different brain regions.

“Anorexia is a serious disorder and there is no existing pharmacological treatment for it. It is therefore important to try out new approaches that can target the core symptoms of the disease, without focusing solely on weight. Having an objective outcome measure, such as BMI, makes it easier to evaluate the effect of the treatment,” says Olea Schau Rybäck, a doctoral student at Lund University and a resident physician within Psychiatry Skåne.

Psilocybin is a naturally occurring psychedelic substance found in certain fungi, often called “magic mushrooms”. As in most other countries, psilocybin is classified as a narcotic in Sweden. It can only be used in research studies where it is possible to administer the drug safely and monitor participants carefully throughout the process. Previous findings in research into depression and PTSD have shown that psilocybin can help break rigid patterns of thought and behaviour. It is hypothesised that psilocybin may affect the synaptic plasticity of the brain, which in turn may also alter thought and behaviour patterns in patients with anorexia.

“The safety study gives us the opportunity to test a potentially effective, but as yet unexplored treatment in patients who have relapsed,” Olea Schau Rybäck continues.

If the researchers find promising results, the idea is to proceed with a larger study focusing more on efficacy and how long the synaptic plasticity in the brain persists.

“The brain is amazing and unpredictable. Psilocybin may open a therapeutic window to create new functional patterns. If the treatment is successful, I see no reason why psychedelic drugs cannot become an established treatment for anorexia nervosa in the future,” concludes Pouya Movahed Rad.

ABOUT THE STUDY
The study is being conducted in collaboration with, among others, doctoral student and resident physician David Sjöström, who works in child and adolescent psychiatry in Skåne. Patients with anorexia nervosa are recruited from all over Region Skåne. All participants must have had contact with psychiatric healthcare and experienced at least one relapse of anorexia nervosa. Alongside conventional care, they will be treated with psilocybin on two occasions. The doses will be given during carefully monitored and therapist-supported sessions, which include checking heart rate, blood pressure and blood sugar. The results are expected to be finalised by the end of 2027.

ANOREXIA NERVOSA
Anorexia nervosa is a serious psychiatric disorder characterised by restricted food intake, intense fear of weight gain and body dysmorphia. Every year, around 8,300 young people are diagnosed with eating disorders in Sweden. Of these, anorexia nervosa is the most common diagnosis among girls aged between 11 and 17. However, a large number of cases remain unrecorded as many people do not seek help.