A psychedelic drug is being tested as a novel way to reduce problematic alcohol consumption, in an ongoing study led by UCL researchers.
The drug, DMT (dimethyltryptamine), is the active ingredient in the Amazonian brew ayahuasca, which has a long history of ceremonial use in South America. In its pure form, DMT is one of the most powerful psychoactive substances found in nature.
The study represents the largest psychedelic brain imaging study of its kind to date and is funded by Wellcome Leap.
A few volunteers have already begun the trial, and the research team is continuing to recruit a total of 120 study participants who drink regularly and are looking to cut back.
Volunteers are given an intravenous dose of the drug, which - unlike other psychedelics - only lasts for 15 minutes, alongside a brief psychological intervention. They also undergo two MRI brain scans while watching a film so that the researchers can examine whether the drug causes lasting changes in brain function. Participants also have an electroencephalography (EEG) brain scan during the dosing session in order to see how the drug impacts brain function while it is active. Volunteers will be given DMT, a placebo or active control drugs (two non-hallucinogenic medications already in common use which may impact brain plasticity) as a comparison.
Volunteers will attend follow-up sessions up to nine months later, so that the scientists can see what impact the intervention has had, and whether it has helped participants to cut back on their drinking.
DMT has been chosen as it is an extremely potent drug that can be administered safely, and because it can impact neuroplasticity - how the brain rewires itself. There's some early evidence that single use in clinical settings can be helpful to treat depression or reduce smoking or opioid dependence.
Professor Ravi Das (UCL Psychology & Language Sciences), co-director of UCL's Clinical Psychopharmacology Unit, who is jointly leading the study, said: "Excessive drinking is partly driven by alcohol hijacking the brain's built-in motivation and reward system. We are seeking to counteract that with our treatment. DMT has some interesting effects on the plasticity of our brains, so we hope it can help 'rewrite' the reward associations people have with alcohol."
Professor Das has previously led a similar study finding that a one-off dose of ketamine, delivered in a targeted way to weaken 'maladaptive rewarding memories' linked to alcohol use, led to a rapid decrease in urges to drink and a prolonged decrease in alcohol intake over nine months.* By using DMT instead of ketamine, the researchers are switching to a drug that is safer and lasts for a shorter period of time, while the new study has the additional benefit of brain scans to offer deeper insight into how the drug affects the brain directly.
Joint study lead Professor Jeremy Skipper (UCL Psychology & Language Sciences) said: "There's a lot of research and excitement about psychedelics in mental health treatments, but not a lot of evidence about what exactly they do, and how they work. We've set up our study to answer these questions, and our study design should enable to pick apart the roles of the drug and the psychological intervention."
Dr Greg Cooper (UCL Psychology & Language Sciences) said: "We hope that our trial not only demonstrates DMT's effectiveness in helping individuals reduce hazardous drinking patterns, but also contributes to the growing evidence that psychedelics, despite their current classification as 'Class A' drugs, can be used safely and effectively to treat mental health disorders. Our findings could help inform evidence-based changes to UK drug policy, allowing these promising treatments to be more widely accessible for those in need."
