Depersonalization-derealization disorder: what it is, symptoms and how it is treated in therapy

Sergio is 20 and in his second year of engineering. One night in March, at a friend's place, he took a few drags of a joint and ten minutes later had the worst panic attack of his life: heart racing, ice-cold hands and the certainty that he was going to die right there. An hour later it was over. What hasn't gone away is what came after. Since that night he sees the world "as if through glass". His bedroom is his bedroom, but it doesn't feel like his; his own voice sounds like someone else talking; he looks in the mirror and his face seems familiar and strange at the same time. He hasn't smoked anything in three months. In the mornings he pinches his arm to check he's still there, and at night he searches his phone for "how to know if I'm going crazy". He isn't going crazy. What he describes has a name, depersonalization and derealization, and it can be treated in therapy.

This guide is written for psychologists who meet these symptoms in their practice, sometimes as the main complaint and sometimes hidden behind anxiety, and also for patients and families looking for reliable information. It covers what depersonalization-derealization disorder is, how it differs from psychosis and from medical causes, how it is assessed and which treatments have support behind them.

What depersonalization and derealization are

Depersonalization is the feeling of being disconnected from yourself: from your body, your thoughts, your emotions. People describe watching themselves "from the outside", like a spectator of their own life. Derealization is the same thing applied to the surroundings: people, objects and places seem unreal, distant, made of cardboard. They can happen separately or together, and most often they come together.

When these experiences keep coming back or never quite leave, cause distress and aren't explained by anything else, the diagnosis is depersonalization-derealization disorder. The MSD Manual Professional Version places it among the dissociative disorders and summarizes the DSM-5-TR criteria like this: persistent or recurrent episodes of depersonalization, derealization or both; reality testing stays intact during the episodes; there is significant distress or impairment in social, occupational or other areas; and the symptoms are not better explained by a substance, by another medical condition (such as a seizure disorder) or by another mental disorder, such as panic disorder, major depression or another dissociative disorder. The WHO's ICD-11 lists it under code 6B66.

The term is more than a century old. It was coined in 1898 by the French psychiatrist Ludovic Dugas, who took it from a note by the philosopher Henri-Frédéric Amiel. Patients then and now reach for almost the same images: feeling "like in a film" or "as if inside a glass box".

Symptoms of depersonalization and derealization

Patients find it very hard to put what is happening into words, and they often arrive convinced that nobody will understand. Yet the phrases repeat a lot from one person to the next, and recognising them is already a relief.

Depersonalization symptoms

• Watching yourself from the outside, as if observing your thoughts, actions or body from a distance.
• Feeling like a robot, not in control of what you say or how you move.
• Your body, or part of it, feeling strange, larger or smaller than normal, or your head feeling "wrapped in cotton wool".
• Emotional numbness: knowing something should make you happy or hurt, and barely feeling anything.
• Memories without emotion, as if they belonged to someone else.

Derealization symptoms

• A sense of living in a dream, in a film or inside a fog.
• A pane of glass or a veil between you and the world, including the people you love.
• Surroundings that look flat, without depth, colourless or artificial; or the opposite, strangely sharp.
• Distances, sizes and shapes that don't add up, and sounds louder or quieter than they are.
• Time running too slowly or too fast, or last week's events feeling as if they happened years ago.

What comes along with it: fear, checking and flattened emotions

The symptoms are almost always distressing and, in severe cases, very hard to bear. Many people fear they have damaged their brain for good or that a psychosis is starting, and that fear drives endless checking: looking in the mirror, touching their face, asking others whether "everything looks the same to them", searching symptoms online or mentally going over whether what's in front of them is real. Some end up stuck on the question of what reality is. That going round in circles, much like rumination, keeps attention glued to the symptom and makes it even more present.

The MSD Manual adds that some people cannot recognise or describe what they feel, which is known as alexithymia, and that anxiety and depression often come with it. Episodes can last hours, days, weeks or months and, in some cases, turn into a constant feeling that rises and falls.

Causes of depersonalization: why it appears

There is no single cause, and often nobody finds out why it started. What is known are the factors that make it more likely and the ones that set off episodes:

• Childhood experiences. Emotional abuse and emotional neglect are especially common in people with the disorder. So are physical abuse, witnessing domestic violence, growing up with a parent who was seriously ill or had a mental disorder, and the unexpected death of someone close.
• Intense stress. Relationship, money or work problems can trigger episodes in people who are already prone to them.
• Anxiety and depression. Above all, anxiety with panic attacks and severe or long-lasting depression. Some people have their first episode in the middle of an attack, like Sergio.
• Drugs. Cannabis, ketamine and hallucinogens can trigger episodes, and it is not unusual to hear that it all started with a joint.
• How a person relates to their own emotions. The Mayo Clinic mentions traits such as a tendency to avoid stressful situations or difficulty describing one's own emotional experience.

In practice, it helps to explain it as a protective mechanism that has stayed switched on. Faced with a threat or an overwhelming emotion, the mind turns down the volume on what is being felt. That disconnection does its job in the moment; the problem starts when it stays, the person gets frightened by it and starts monitoring it.

How common is depersonalization? When does it start?

One-off experiences are very common: according to the MSD Manual, between 25% and 75% of people have had at least one in their lifetime. The disorder, on the other hand, affects around 1-2% of people, men and women in equal numbers.

It usually starts early. The average age of onset is 16, it can begin in childhood, only 5% of cases start after 25, and onset after 40 is rare. The practical difference between a passing experience and the disorder looks like this:

What matters day to day is whether the feeling comes back, whether it lasts and whether it is taking things away: studies, work, relationships or the will to leave the house.

Depersonalization in teenagers

With such an early age of onset, many cases show up in adolescence or the first years of university, and many show up late: the young person can't explain it, is afraid of being taken for crazy and hides it. It helps families to understand that this is a known, treatable symptom, not to ask every hour whether they are "better yet" and not to turn every episode into an emergency. In therapy with teenagers, agree from the start what will be shared with the parents and what won't.

Depersonalization, anxiety and psychosis: the differential diagnosis

Depersonalization is a symptom that appears in many conditions, so other explanations have to be ruled out before calling it a disorder:

• Panic disorder. Feeling unreal during an attack is common, but it goes away when the attack passes. If that is the only time it appears, what needs treating is panic disorder.
• Major depression. The emptiness and emotional numbness of depression can look very similar.
• Trauma. Post-traumatic stress disorder has a dissociative subtype with persistent depersonalization or derealization, and other dissociative disorders include it too.
• Psychosis. In psychosis, reality testing is lost: the person believes the world has really changed or that someone is controlling their thoughts. In depersonalization it is preserved.
• Substances and medical causes. Drug use, the effects of some medications, epilepsy and other neurological conditions.

When medical tests are needed

If the picture is atypical or begins after the age of 40, the MSD Manual advises ruling out structural causes with an MRI and an EEG, and sometimes a urine drug screen. Any added neurological symptom also deserves a medical assessment, such as loss of consciousness, involuntary movements or memory gaps. The psychologist doesn't order those tests, but knows when to refer and to whom.

How depersonalization is assessed in practice

The interview

The interview covers when it started and what was going on at the time (a panic attack, drug use, a very stressful period), how it has evolved since, what makes it worse and what eases it, whether there is cannabis or other substance use, how the person sleeps, whether there is a history of trauma or emotional neglect, and what they do when they notice the symptoms: checking, avoiding, searching online, asking others. Reality testing, anxiety, mood and the risk of self-harm also need exploring, because some patients arrive very desperate.

Scales to measure depersonalization

The most widely used is the Cambridge Depersonalisation Scale (CDS), with 29 items, which scores the frequency and duration of each experience and is useful for tracking change during treatment. The Dissociative Experiences Scale (DES), with 28 items, gives a broader view of dissociation. For a fuller assessment there are structured interviews and the Multidimensional Inventory of Dissociation (MID), which the MSD Manual mentions.

The episode log

A simple log kept for a few weeks reveals patterns: day and time, intensity from 0 to 10, where they were and with whom, what happened before (an argument, a bad night, a joint) and what they did afterwards. Almost always something turns up that the patient hadn't noticed, for example that it gets worse when they are home alone or better when they are busy with something else.

Treatment of depersonalization-derealization disorder

The main treatment is psychotherapy. If anxiety or depression are also present, they are treated too, sometimes with medication. There is no specific clinical guideline like the ones for depression or OCD (the UK's NICE, for instance, has none for this disorder), so the work rests on small studies and accumulated clinical experience. The NHS describes the aim of talking therapies as helping people cope with the underlying cause and practise techniques for the periods of feeling disconnected.

Psychoeducation: understanding what is going on

Often the first relief comes in the first session, when the patient hears that what is happening to them has a name, that it happens to many other people and that it is not the beginning of a psychosis. Presenting depersonalization as a protective response that has stayed switched on takes away the sense of catastrophe and prepares the rest of the work.

Cognitive behavioural therapy for depersonalization

It is the most studied approach. Elaine Hunter's team in London published an open study in 2005 with 21 patients treated with cognitive behavioural therapy who improved significantly, and in 2025 a randomised feasibility trial with 30 participants that compared it with usual treatment. The results were promising, and the authors themselves call for a larger trial before drawing firm conclusions. In practice, the work usually includes:

• Testing catastrophic interpretations ("I'm going crazy", "I'll never be myself again") against the person's own experience.
• Gradually cutting down the checking: the mirror, the pinching, the searches, the questions to others.
• Getting back the activities dropped out of fear that the symptoms would get worse.
• Training attention so it stops sticking to the symptom and returns to whatever the person is doing.

Grounding techniques with the five senses

Grounding techniques bring attention back to the present through the senses. The MSD Manual gives examples as simple as listening to loud music or holding an ice cube. Another widely used one is 5-4-3-2-1: naming five things you can see, four you can touch, three you can hear, two you can smell and one you can taste. They don't make depersonalization disappear, but they lower the intensity of the moment and give the person something to do other than checking. Mindfulness and naming emotions during the session also help some people.

Working on the trauma and the underlying anxiety

When there is childhood emotional abuse or neglect behind it, or very intense anxiety, treatment has to reach that too. According to the MSD Manual, psychodynamic therapy helps some patients manage the underlying conflicts and the intolerable feelings that trigger dissociation. With trauma, the work tends to take longer and needs a pace the patient can sustain.

What about medication?

No drug has clearly proven effective for depersonalization itself. SSRI antidepressants, lamotrigine, opioid antagonists, anxiolytics and stimulants have been tried, and some patients improve with them, probably because they act on the anxiety or depression that comes with it. The decision belongs to psychiatry, and working in coordination makes sense.

Prognosis: can depersonalization be cured?

It can resolve completely, especially when the trigger is treatable or was temporary and when the symptoms haven't lasted long. In other people it becomes chronic and harder to shift. Even then, some manage to make the feeling weigh very little in their lives by keeping busy and no longer monitoring it, while others are badly limited by the constant strangeness or by the anxiety and depression that come with it. That is why early treatment matters.

How to get rid of the feeling of unreality: tips for daily life

People who look up how to get rid of the feeling of unreality usually hope for a trick that switches it off at once. That trick doesn't exist, and looking for it is part of the problem. What does help:

• Naming it instead of fighting it: "this is depersonalization, it's unpleasant and it isn't dangerous".
• Stopping the checking. Every time someone looks in the mirror to see if they are still themselves, attention goes back to the symptom.
• Carrying on with life: going to class or to work, seeing friends, even with the feeling in the background.
• Grounding through the senses at the most intense moments.
• Looking after the basics: sleeping at regular times and not using cannabis or other drugs, which can trigger episodes.
• Logging the episodes for a few weeks to see what makes them worse and what doesn't.

Depersonalization: when to seek professional help

A single episode of depersonalization is no cause for alarm. As the Mayo Clinic advises, it is worth seeing someone when the feeling bothers you or upsets your emotions, doesn't go away or keeps coming back, or gets in the way of work, relationships or everyday activities.

How to document follow-up in depersonalization

With a problem the patient experiences as permanent, seeing change written down helps a great deal. It is worth recording at each session:

• The CDS score at the start and every so often, for example once a month.
• The week's episodes from the log: how many, how long they lasted and how intense they were.
• The checking and avoidance that remain and what has already been dropped.
• The triggers that come up and what was agreed for the following week.

Reviewing that data with the patient every few weeks shows progress that is very hard to notice with the feeling of unreality still around.

Depersonalization in your practice with My Psico Agenda

My Psico Agenda doesn't assess or treat anyone: that is your job. What it does is keep everything around a treatment like this in order:

• Notes for every session. In each appointment's "Details / Notes" you record the CDS score, what came out of the log and what was agreed for the week, and the patient's "Clinical History" holds the case summary.
• Your own fields in the record. Under "Additional data" you add the fields you need, such as "Baseline CDS", "Triggers" or "Cannabis use". If you work in a centre, the centre can also add its own "Centre fields", shared across all its therapists' records.
• The log in the patient's hands. You upload the template to "Patient files". It goes up as "Hidden"; when you switch it to "Visible", the patient finds it in their space under the "Documents" tab, and in the record you see "Seen" with the date they opened it.
• Teenagers and their family. If you tick "Minor patient?", the record belongs to the minor and stores the details of "Guardian 1" and, if there is one, "Guardian 2". The informed consent can be signed by the guardians, each with their own link or on your own device.
• The details, before the first session. With "Send form to the patient" you send them a link so they can fill in their details on their phone and, if you turn it on, sign the consent on that same page.
• A fixed slot every week. With "Recurring therapy" you book their slot, and they get a WhatsApp reminder 24 hours before with buttons to confirm or cancel.
• The clinical history, behind a PIN. In Settings ▸ Security you can require a PIN for "View clinical history", useful if other people use the practice computer.
• Consistency, in numbers. In each patient's statistics you see "Total sessions", "Attendance" and "Cadence".
• Who has stopped coming. "See inactive patients" shows the people who have gone two months without a session and have nothing booked, with a "Contact on WhatsApp" button. Someone who withdraws and stops coming without a word deserves a call.

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