Does Ketamine Therapy Get You High?

The short answer: ketamine therapy produces an altered state of consciousness, but calling it a "high" misrepresents what's actually happening. Sub-anaesthetic clinical doses produce a temporary dissociative experience — patients commonly describe feeling like they're floating, observing thoughts from a slight distance, or noticing altered time and perception. The experience is supervised, time-limited (usually 45 to 90 minutes), and clinically expected. It is not euphoria, not intoxication in the recreational sense, and not "losing control." This guide explains what ketamine therapy actually feels like, why it differs from recreational use, and how Canadian clinics manage the experience.

Key takeaways

• Ketamine at therapeutic doses produces dissociation — a clinical term distinct from recreational "high."
• Patients commonly report altered time perception, mild visual or auditory shifts, emotional softening, and a sense of distance from habitual thoughts (van Schalkwyk et al., 2018).
• The experience typically lasts 45 to 90 minutes and resolves before the patient leaves the clinic.
• Therapeutic and recreational ketamine differ in dose, setting, supervision, and integration — not just one variable.
• Bladder and hepatic toxicity associated with ketamine are linked to high-frequency, high-dose recreational exposure, not therapeutic clinical dosing.

The short answer — and why "high" doesn't quite fit

The word "high" carries recreational connotations: euphoria, intoxication, pleasure-seeking. Ketamine therapy is something different. Doses are sub-anaesthetic — significantly lower than recreational quantities. The setting is a supervised clinical environment with vital-sign monitoring. The intent is therapeutic processing, not intoxication. Integration psychotherapy is built into the treatment.

What patients do experience is dissociation — a temporary altered state where ordinary boundaries between self and environment soften. This is a recognized clinical term, not a synonym for "high." Dissociation is the mechanism through which ketamine produces its rapid antidepressant effect; it is not a side effect to be suppressed.

Atomic answer. Ketamine therapy produces an altered state, but calling it a "high" misrepresents the experience. In a clinical setting, ketamine is administered at sub-anaesthetic doses while a trained care team monitors you throughout. Most patients describe a dreamlike calm, a sense of floating, or mild emotional distance from their thoughts. These sensations typically last 45 to 90 minutes and resolve completely before you leave the clinic. The key difference from recreational use is not just dosage but context: therapeutic ketamine is delivered with a clear clinical intention, professional oversight, and integration support after the session. The dissociative state is a side effect of the mechanism, not the goal. The goal is lasting relief from depression, anxiety, or PTSD — not intoxication.

What ketamine actually does to your brain

Ketamine acts at NMDA (N-methyl-D-aspartate) receptors. At sub-anaesthetic doses, it produces a measurable dissociative experience — a class of altered state established in the foundational 1994 trial by Krystal et al., where 19 healthy subjects received subanesthetic ketamine and demonstrated "a broad range of symptoms…that resemble aspects of dissociative states" (Krystal et al., 1994).

Mechanistically, NMDA antagonism triggers a downstream surge of glutamate, AMPA receptor activation, and BDNF release that drives synaptogenesis — the formation of new neural connections within 24 to 72 hours of a dose (Kang et al., 2022; Zanos & Gould, 2018). The dissociative experience and the antidepressant effect emerge from related neural processes; the experience is not separable from the mechanism.

What's important: the dose determines the character of the experience. Anaesthetic doses produce unconsciousness. Sub-anaesthetic clinical doses produce dissociation while preserving consciousness, communication, and responsiveness. Recreational doses sit somewhere on this curve, typically higher than therapeutic and lower than anaesthetic, taken without screening or monitoring.

What the experience actually feels like — session by session

Clinical and qualitative research documents what patients commonly describe. These are group-level findings, not individual guarantees.

In a mixed-methods analysis of 110 patients receiving IV ketamine for mood disorders, van Schalkwyk et al. (2018) found that "five of the six highest loading items involved perceptual disturbances, either of time or sensation"; in-depth interviews additionally identified disinhibition and a sense of peace (van Schalkwyk et al., 2018). A 2024 qualitative study of IV ketamine in patients with alcohol use disorder reported the most frequently assigned themes as "Meaningful, spiritual, and mystical experiences," "Positive affect," and "Inherent contradictions of the acute experience" (Terasaki, 2024).

Patient descriptions cluster around several categories:

• Time distortion — minutes feeling like hours; or hours compressing into what feels like a brief interval.
• Floating or weightlessness — a sense of physical buoyancy or ungroundedness.
• Mild visual or auditory shifts — soft colours behind closed eyes; geometric patterns; music sounding more vivid than usual.
• Emotional softening — distance from anxious or depressive thought patterns; feelings observed rather than experienced from inside.
• Sense of peace or quiet — a subset of patients describe a calm distinct from sedation.
• Spontaneous insight — connections to memories, relationships, or recurring patterns surfacing without effort.
• Inherent contradictions — described as "everything and nothing at once" or "lonely yet connected."

Not every patient has every experience. Some find the session profoundly meaningful; others find it simply calm; a smaller number find it anxiety-inducing or unsettling, particularly trauma survivors processing difficult material. The acute experience typically lasts 45 to 90 minutes and resolves within the post-session monitoring window.

Will you hallucinate? What about a "bad trip"?

Sub-anaesthetic clinical doses of ketamine do not reliably produce full hallucinations. Mild perceptual shifts — soft colours, geometric patterns, altered time perception — are common. Full loss of contact with reality is rare at therapeutic doses with proper screening.

The "bad trip" framing is recreational-context language. In clinical settings, two structural factors substantially reduce the risk of difficult experiences becoming destabilizing:

1. Set and setting are managed. Patients are screened for psychiatric stability. Preparation sessions establish intentions and address anxieties before dosing. The treatment environment is calm, controlled, and predictable. The clinical team is present throughout.

2. Difficult material is anticipated and held. When emotional or memory content surfaces during a session — and for many patients it does — the therapist's role is to support processing, not minimize it. Integration sessions afterwards translate the experience into sustained behavioural change.

Hartogsohn (2016) framed this in pharmacology terms: "set and setting theory is primarily prescriptive, educating therapists and users on how to control and optimize the effects of drugs" (Hartogsohn, 2016). The same molecule produces meaningfully different experiences depending on the context in which it is administered. A 2020 systematic review of 34 experimental studies concluded that "with proper screening, preparation, supervision, and integration, limited aversive side effects were noted by study participants" (Aday et al., 2020).

Therapeutic ketamine vs. recreational ketamine — the four differences

Two parameters that matter clinically, and two that matter contextually:

These four variables compound. A clinical session is not just "the same drug as recreational use, but in a clinic." The dose is different, the setting is different, the supervision is different, and the integration around the session changes whether material that surfaces during the experience translates into sustained change or simply fades. Sassano-Higgins et al. (2016) document that recreational use is associated with "disinhibition and altered sensory perceptions [that] put users at risk of environmental harm" — a risk pattern that does not arise in clinical contexts (Sassano-Higgins et al., 2016).

Is dissociation dangerous? Understanding what it does for healing

The word "dissociation" can be alarming. In everyday speech it sometimes implies disorientation or impairment; in psychiatry it can refer to trauma-driven detachment that is clinically problematic. The dissociation produced by ketamine at therapeutic doses is none of these things.

Pharmacologically, dissociation under ketamine is a temporary state in which the normal integration between sensory input and self-referential processing is briefly disrupted. Patients can communicate. They are aware of the room and the clinician. They are not unconscious. The experience resolves within hours.

There is an emerging clinical hypothesis that the dissociative window itself contributes to therapeutic benefit — that a temporary distance from habitual self-referential thinking creates an opportunity for new patterns to form. The Roseman et al. (2018) analysis of psilocybin trials found that the intensity of "oceanic boundlessness" during dosing predicted antidepressant outcomes (Roseman et al., 2018). Murphy et al. (2022) showed that the strength of therapeutic alliance predicted both the quality of the acute experience and final depression scores in psilocybin therapy (Murphy et al., 2022). The clinical dissociative state appears to interact with the therapeutic relationship in ways that ordinary pharmacology does not capture.

What dissociation is not: psychosis. The two are distinct phenomena. Active psychosis or schizophrenia spectrum disorder is an absolute contraindication to ketamine therapy precisely because the clinical team needs to be confident that any altered-state experience the patient has during a session is the controlled, time-limited dissociation that ketamine reliably produces — not the destabilizing decompensation that psychotic illness can produce.

Is ketamine therapy addictive?

At therapeutic doses in supervised clinical contexts, dependency risk is low. The pattern that drives ketamine addiction — frequent unsupervised use at high doses over months or years — does not occur in clinical protocols. Sessions are scheduled, doses are calibrated, the substance is administered by clinicians, and patients do not have access to ketamine between sessions.

The CANMAT 2021 task force noted that misuse risk should be assessed but considers it manageable in well-screened patients on standard protocols. Active ketamine use disorder is an absolute contraindication. For patients with histories of other substance use disorders, eligibility is case-by-case after a stabilization period.

A systematic review of oral ketamine in depression and pain found the drug "appears well tolerated" at the described clinical doses, while flagging the field's need for more rigorous longer-term safety data (Schoevers et al., 2016).

Is ketamine safe? What the long-term data show

At sub-anaesthetic doses with proper screening, ketamine has a well-established short-term safety profile. Across 205 IV infusions in 97 patients with treatment-resistant depression, the pooled safety analysis found ketamine "safe and well tolerated"; hemodynamic changes were transient; no persistent psychotomimetic effects or increased substance use were observed at long-term follow-up (Murrough et al., 2015).

For Spravato (intranasal esketamine), the SUSTAIN-2 long-term safety study followed 802 patients for up to a year. Adverse effects including dissociation were predominantly mild to moderate, occurred on dosing days, and resolved rapidly. Notably, "no cases of serious complications such as interstitial cystitis or respiratory depression were observed" over the trial period (Wajs et al., 2020).

The 2017 American Psychiatric Association consensus statement on ketamine in mood disorders recommends careful patient selection and structured clinical oversight given the drug's complex risk-benefit profile (Sanacora et al., 2017).

Common short-term side effects in supervised settings:

• Dissociation during the dosing window (intended)
• Mild nausea
• Transient elevation in blood pressure (typically 10–30 mmHg) and heart rate
• Dizziness or unsteadiness
• Headache

These resolve within the post-session monitoring window. Patients cannot drive for at least 24 hours after a session.

The bladder, the liver, and the recreational distinction

Ketamine-associated bladder damage (ulcerative cystitis) was first documented in case series of chronic recreational users — patients consuming gram-level quantities frequently over extended periods (Shahani et al., 2007). A subsequent comprehensive review found that "regular ketamine consumption has been shown to increase the risk of cystitis symptoms by 3- to 4-fold, and cessation of ketamine use is usually associated with improvement of symptoms" (Anderson et al., 2022).

Ketamine-induced cholangiopathy — biliary tract and hepatic damage — has been documented in chronic heavy recreational users as well, often co-occurring with the bladder findings (Nazir et al., 2025).

These toxicities are linked to dose, frequency, and duration of exposure that far exceed clinical protocols. SUSTAIN-2 (n=802 over up to a year) observed no cases of interstitial cystitis. That said, Health Canada has issued safety guidance noting hepatotoxicity and cholangiopathy risk with extended ketamine exposure; baseline and ongoing liver-function monitoring is appropriate for patients receiving maintenance infusions over long time horizons.

For patients with pre-existing urological or hepatic conditions, this is a discussion to have explicitly with the prescribing physician at intake.

What to expect at an ATMA CENA session — before, during, and after

Before. Patients arrive having fasted (typical for IV protocols) or eaten lightly per program instructions. Vitals are checked. The clinical team reviews intentions and any specific concerns. Patients are settled in the treatment space — typically a quiet, comfortable room.

During. The dose is administered — IV over 40 minutes, IM as a single injection, sublingually held under the tongue, or Spravato as a nasal spray. Effects begin within minutes. The acute experience lasts 45 to 90 minutes. The therapist or nurse stays with the patient throughout. Monitoring is continuous. Patients can communicate and ask questions; some prefer eye shades and music to deepen the inward experience, while others prefer to remain in conversation with the therapist (the difference between ATMA CENA's psychedelic and psycholytic dosing modes).

After. Patients rest in a recovery setting for another 30 to 60 minutes (longer for Spravato — Health Canada requires a minimum 2-hour observation). Vitals are re-checked. The clinical team confirms the patient is stable before discharge. Patients cannot drive for at least 24 hours and need an escort home.

Integration. In the days and weeks following each dose, integration sessions with the therapist process the material that surfaced during the experience. This is where the work of translating insights into sustained behavioural change happens. A 2017 trial demonstrated that adding 12 weeks of CBT after a 4-session IV ketamine course extended antidepressant durability — relapse occurred in only 25% of responders by week 8 versus 55–89% in comparable open-label ketamine-only protocols (Wilkinson et al., 2017).

Who is a good candidate — and who should think carefully

Ketamine therapy is most established for treatment-resistant major depressive disorder. Other indications (PTSD, anxiety, OCD, chronic pain) are evaluated individually.

Conditions that disqualify treatment include active psychosis or schizophrenia spectrum disorder, uncontrolled severe hypertension, severe cardiovascular disease, increased intracranial pressure, current pregnancy, anaphylactic reaction to ketamine, active manic episode, and active ketamine use disorder.

Conditions that require careful evaluation include history of substance use disorder, severe personality disorder with marked instability, recent stroke, untreated severe sleep apnea, and concurrent use of MAOIs or high-dose benzodiazepines. For full eligibility detail, see How to Qualify for Ketamine Therapy in Canada.

Patients who are anxious about the dissociative experience, who have a strong personal aversion to altered states, or who are processing significant unresolved trauma should discuss these factors openly with the clinical team during intake. The screening process is not a formality — it exists to match patients with the modality and care plan most likely to benefit them.

Frequently asked questions

Does ketamine therapy make you feel high? Ketamine produces an altered state — dissociation — at therapeutic doses, but the word "high" carries recreational connotations that don't fit the clinical context. Doses are calibrated for therapeutic effect, not euphoria; the setting is supervised; the goal is psychological processing, not intoxication. The dissociative experience resolves within hours and patients return to ordinary cognition before leaving the clinic.

What does ketamine therapy feel like? Patients commonly describe altered time perception, a floating or dreamlike quality, mild visual or auditory shifts, an emotional softening, and a sense of distance from habitual thought patterns. Clinical literature documents these as expected aspects of the dissociative state at sub-anaesthetic doses. The experience is highly individual.

Is ketamine therapy a psychedelic? Ketamine is technically classified as a dissociative anaesthetic rather than a classical psychedelic. The mechanism (NMDA antagonism) differs from classical psychedelics like psilocybin (5-HT2A agonism). However, at sub-anaesthetic doses ketamine produces an altered state that shares features with classical psychedelic experiences, which is why ketamine-assisted therapy is sometimes grouped under the broader "psychedelic-assisted therapy" umbrella.

Can ketamine therapy cause hallucinations? Sub-anaesthetic clinical doses do not reliably produce full hallucinations. Mild perceptual shifts — soft colours behind closed eyes, geometric patterns, altered time perception — are common. Full loss of contact with reality is rare at therapeutic doses with proper screening.

Can you have a "bad trip" during ketamine therapy? The "bad trip" framing is recreational-context language. Difficult experiences during clinical sessions can occur, particularly for patients processing trauma, but the clinical setting is structured to support such experiences rather than amplify them. The therapist is present throughout; integration sessions afterwards translate difficult material into sustained processing.

How long do the effects last? The acute dissociative experience typically lasts 45 to 90 minutes and resolves before the patient leaves the clinic. Antidepressant effects from a single dose can emerge within 2 to 72 hours and last days to weeks. Patients cannot drive for at least 24 hours after a session.

Is ketamine therapy safe in Canada? At sub-anaesthetic doses with proper screening and supervised administration, ketamine has a well-established short-term safety profile. Provincial physician colleges (CPSA, CPSM, CPSO, CPSBC) regulate where and how IV ketamine can be administered; clinics meeting these standards operate within established Canadian medical safety frameworks.

Is ketamine therapy addictive? At therapeutic doses in supervised clinical contexts, dependency risk is low. The pattern that drives ketamine addiction — frequent unsupervised use at high doses — does not occur in clinical protocols. Active ketamine use disorder is an absolute contraindication for ketamine therapy.

Sources

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Last updated: 2026-05-05