How psychedelic therapy works
In mental health conditions, the brain gets stuck in a loop of negative thinking and rumination, which is linked to overactivity of the part of your brain responsible for daydreaming and self-reflection called the default mode network (DMN). Psychedelics, such as psilocybin and lysergic acid diethylamide (LSD), have been shown to disrupt the DMN and break down this loop, allowing other parts of the brain to communicate with each other (Cameron et al., 2023). This lets your brain see things differently, potentially allowing you to gain new insights.
What conditions is it used for
Depression and treatment-resistant depression
Post-traumatic stress disorder (PTSD)
Anxiety disorders
End-of-life anxiety and depression
Obsessive compulsive disorder (OCD)
Addiction, including smoking and alcohol use disorder
Eating disorders, including anorexia nervosa and bulimia
Chronic pain conditions, such as migraine and fibromyalgia
Neurodegenerative disorders, including Parkinson's disease and Alzheimer's
What to expect during treatment
Even with a controlled dose, how the experience will feel is hard to predict and can vary significantly from person to person. People describe seeing vibrant colors and vivid visuals and reliving memories. Some describe a feeling of timelessness and floating and compare it to an out of body experience. A dissolution of one's ego and a greater sense of self are also commonly reported.
Though the experience itself can't be predicted, here is a general overview of what to expect from a psychedelic therapy session.
Assessment
Before starting psychedelic-assisted therapy, you'll undergo a comprehensive psychological and medical assessment to determine if it's right for you. This will include a thorough review of your mental health and physical health history, which will include details about any medications you take or recreational drugs you use.
Informed consent is required before starting psychedelic therapy. The treatment, including potential risks, will be explained to you before you begin.
Preparation
If you're a suitable candidate for psychedelic therapy, you will have pre-treatment sessions with a therapist to help you understand how the treatment works and what to expect during your experience. During these sessions, the therapist may work with you to set intentions for your treatment. This is also an opportunity to build trust with the therapist ahead of your first treatment session.
Set and setting is key for a successful psychedelic therapy session. Set refers to your mindset and the setting refers to the environment. Because psychedelics intensify the internal and external conditions, psychedelic therapy may be best suited to people who are ready and willing to prepare for their sessions, including making some lifestyle modifications.
Your therapist can help provide a safe, secure, and comfortable environment for your session, but there are healthy modifications you can make to prepare your mindset. Refraining from alcohol and other drugs and substances is advised. Getting good sleep, lowering your stress, eating healthy, and staying hydrated can all help prepare your emotional state, your body, and your brain for the experience.
You cannot drive after your treatment and should plan to have a responsible adult drive you home.
Dosing session
The treatment will take place in a calm, secure environment. The therapist will provide sensory aids, such as blankets, music, and eye masks to help you feel comfortable and safe throughout your experience.
You will be administered the psychedelic substance, which will be in pill or capsule form, and get comfortable for the experience. The therapist will be with you throughout the experience to support you and ensure your safety.
You should expect the session to last anywhere from 4 to 8 hours, depending on the substance used.
Integration
Integration refers to the follow-up therapy sessions you will undergo to help you process your experience. This begins immediately after the experience where you will discuss the experience with your therapist. They will help you integrate the insights gained during your experience and show you how to turn them into behavioral changes that you can use in your daily life moving forward.
The mechanism in depth
Psychedelics also activate 5-HT2A serotonin receptors in the brain, which play an important role in mood, perception, and cognition. They also aid in neuroplasticity and help form new neural pathways, which can last for months. During this time, your brain is more receptive to change, giving you time to reframe negative thoughts and gain more from therapy.
MDMA works differently. It helps to quiet the amygdala, which is the part of your brain that's primarily responsible for emotional processing, mainly fear and anxiety. By quieting this part of the brain, it becomes easier to open up and revisit past traumas without fear and panic, which is why it's sometimes used to treat PTSD. MDMA also increases oxytocin, which is a hormone that's often referred to as the "love hormone" or "happy hormone" because it enhances trust, bonding, and communication. This may help create a stronger connection between a patient and therapist (Riaz et al., 2023).
Common uses
Psychedelic therapy may be most beneficial for people living with depression, anxiety, PTSD, and certain types of addiction, as well as those with obsessive compulsive disorder who have been deemed treatment-resistant after trialing different medications without relief.
Interest in the therapeutic benefits of psychedelics has increased significantly in recent years and there are currently hundreds of clinical trials underway in the United States and the rest of the world (Harvey & Nemeroff, 2026).
What the evidence supports
Psychedelic therapy is seen as a new and emerging approach to treating psychiatric conditions and research has boomed in recent years, but research into the therapeutic benefits actually began in the 1940s with the discovery of LSD. It continued until the 1960s when recreational use of psychedelics increased, ultimately leading to the criminalization of psychedelics.
More recently, research has found significant evidence to support the use of psychedelic therapy across a wide range of mental health conditions.
A systematic review of 10 millennial era psychedelic therapy trials conducted between 2000 and 2020 found long-lasting therapeutic effects after only 1-3 sessions in people with those with depression, anxiety, OCD, and substance use disorders (Andersen et al., 2021).
A 2020 meta-analysis of 9 placebo-controlled trials confirmed that psychedelic-assisted therapy is highly safe and effective, and able to provide better clinical benefits from limited sessions compared to daily medications or psychotherapy alone for those with PTSD and anxiety/depression related to life-threatening illness (Luoma et al., 2020).
More recently, a review of 23 meta-analyses covering over 100 studies found that psychedelic therapy could effectively treat PTSD, depression, addiction, and neurodevelopmental disorders. Psilocybin-assisted therapy for depression and MDMA-assisted psychotherapy for PTSD were shown to have particularly significant and lasting benefits, as well as a good safety profile (Dominiak et al., 2025).
Where the evidence is limited
While preliminary studies show that psychedelic therapy may effectively treat mental health conditions like depression and PTSD, more research is needed to address some gaps in the evidence.
Long-term studies are needed to confirm whether the effectiveness of psychedelic therapy lasts beyond a few weeks or months and to determine the long-term safety risks, if any.
More research is also needed to determine the best type of psychotherapy to accompany psychedelics or whether therapy always needs to be combined with psychedelic treatments at all, as some researchers question when and if it will help (Zamaria et al., 2025).
Finally, while benefits of psychedelic therapy for the treatment of depression and PTSD are well known, more research is needed to confirm effectiveness for other mental health conditions and addiction.
Safety and regulations
Research suggests that psychedelic therapy can be safe and effective as a treatment for certain mental health conditions and offer patients lasting benefits, but safety standards and treatment protocols need to be established.
In the meantime, choosing a qualified therapist who has been trained in psychedelic-assisted therapy is crucial for a safe and effective outcome, as is a thorough evaluation of your mental health history and medical history.
Although it's generally safe, psychedelics do carry the risk of side effects even in therapeutic doses. Your provider should explain the psychological and physical risks with you, which include anxiety and emotional distress, and increased heart rate and blood pressure. There is also a small risk of psychosis, especially in people with schizophrenia (Sabé et al., 2025).
Post-psychedelic trauma is another rare but possible complication that can occur when a person has an intense or terrifying experience during their session that they're not able to emotionally process. This can result in lasting symptoms of PTSD that can leave a person feeling disconnected from their surroundings.
Another rare complication is a condition called Hallucinogen Persisting Perception Disorder (HPPD) in which a person continues to experience or re-live visual disturbances from their psychedelic experience for days, weeks, or months after. They may see halos, bright lights, or other visual disturbances that can cause significant fear and chronic anxiety despite being fully coherent and aware that the distortions are not real.
Psychedelic therapy is not recommended for people with uncontrolled medical conditions, such as hypertension or cardiovascular conditions, a history of psychosis, or those who are pregnant.
Again, choosing a qualified professional is important to lower the risk of complications and help ensure a safe and effective experience.
The future of psychedelic therapy
Unlike traditional treatments, which involve taking medication daily to manage symptoms, psychedelic therapy has been shown to work much faster, often providing long-lasting results after just a few sessions. With studies showing that nearly 30 percent of people with depression don't respond to antidepressant medications (McIntyre et al., 2023), there's an urgent need for new and integrative approaches.
Research into psychedelic treatments for a range of mental health conditions is rapidly evolving, being accelerated by the need for better treatments for those with treatment-resistant conditions. Along with many clinical trials entering phase 3, the legal landscape of psychedelic therapy is also shifting with more governments decriminalizing psychedelics and allowing regulated access.
While more blinded studies with long-term follow-up are needed to establish standard dosing, treatment, and safety guidelines, the current pace at which the field is moving suggests that's on the horizon.
Takeaway
Psychedelic therapy shows promising potential for helping people manage complex mental health challenges like depression and PTSD, even when other treatments have failed. With support and guidance from a trained therapist, you can start your path to healing.
