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ketamine

Adjunctive therapy

Brand: Ketalar

Published 2025-12-23 · Last reviewed 2025-12-30 · 4 references

Content sourced from FDA labeling (DailyMed) and peer-reviewed literature.

Print sheet Review evidence

At a glance

Class: Adjunctive therapy·Typical dose: Label dosing depends on the clinical indication (anesthesia/sedation) and route (IV or IM). Dosing for psychiatric indications is off-label (label/consensus).·Half-life: Single-dose mean 2.5 h·LAI available: No

Class: Adjunctive therapy
Typical dose: Label dosing depends on the clinical indication (anesthesia/sedation) and route (IV or IM). Dosing for psychiatric indications is off-label (label/consensus).
Half-life: Single-dose mean 2.5 h
LAI available: No

Quick answers

What is ketamine?: Ketamine (brand Ketalar; generics) is a dissociative anesthetic (label) and non-competitive NMDA receptor antagonist. In psychiatry it is most often discussed as an off-label, rapid-acting option for treatment-resistant depression (TRD) delivered in a monitored setting (consensus).
What is Ketalar?: Ketalar is a brand name for ketamine.
What is Ketalar (ketamine) used for?: Label indications include: Anesthesia (label). Off-label: rapid-acting treatment in monitored settings for treatment-resistant depression and acute suicidal ideation (consensus/clinical).
What drug class is Ketalar (ketamine)?: NMDA Antagonist.
What is the mechanism of action of Ketalar (ketamine)?: Dissociative anesthetic and non-competitive NMDA receptor antagonist. Used clinically for anesthesia (label) and increasingly used off-label in monitored settings for rapid symptom relief in treatment-resistant depression (consensus/clinical).
What strengths does Ketalar (ketamine) come in?: Injectable solution for IV/IM administration (label).

General information

Ketamine (brand Ketalar; generics) is a dissociative anesthetic used for anesthesia and procedural sedation (label). It is increasingly used off-label in monitored settings for treatment-resistant depression (TRD) and acute suicidal ideation, based on rapid-onset antidepressant effects in some patients (consensus/clinical).

Unlike Esketamine (Spravato), ketamine is not FDA-approved for depression. Most psychiatric protocols treat ketamine as a monitored procedure with structured symptom tracking rather than a take-home prescription (consensus).

Acute effects can include dissociation and short-lived sedation, which is why protocols commonly include on-site observation and functional safety planning (transportation and activity restrictions) after the session (consensus/clinical).

Ketamine can increase blood pressure and heart rate during administration, so screening and session vital sign monitoring are typical (label/consensus).

The compare view, ketamine evidence feed, and ketamine print page help align expectations about rapid symptom change with the safety and access logistics of treatment.

U.S. approvals

Anesthesia and procedural sedation (label)

Formulations & strengths

Injectable solution for IV/IM administration (label).

Generic availability

Generic ketamine injection widely available; Ketalar is a branded product.

Ketamine use for depression is off-label and typically delivered in clinics that can monitor vitals and mental status during and after the session. Access, cost, and local protocol variability are common practical considerations.

View labelExact

Mechanism of action

Refer to the Glossary entry on Neurotransmitters for background on receptor systems involved in serious mental illness.

Non-competitive NMDA receptor antagonism alters glutamatergic signaling, producing dissociation at higher exposures and, in some patients, rapid-acting antidepressant effects at subanesthetic exposures (mechanism/consensus).

Downstream synaptic plasticity and circuit-level changes are proposed mechanisms for mood improvement; ketamine’s metabolite norketamine also has NMDA activity (label/mechanism).

NMDA receptor antagonism; dissociative anesthetic effects.

Metabolism & pharmacokinetics

Ketamine is metabolized via N-dealkylation to norketamine primarily by CYP2B6 and CYP3A4 (label).
Label describes a redistribution (beta) half-life of ~2.5 hours after IV administration; clinical effects of anesthesia are shorter than the beta phase (label).
Norketamine is the major circulating metabolite and has NMDA activity but lower affinity than ketamine (label).

Dosing & administration

Label dosing depends on the clinical indication (anesthesia/sedation) and route (IV or IM). Dosing for psychiatric indications is off-label (label/consensus).
Consensus statements for mood disorders describe commonly used monitored infusion protocols (often weight-based over a short infusion) with observation during and after the session (consensus).
When ketamine is used repeatedly, protocols often include structured symptom rating and reassessment of ongoing need, because benefit can be rapid but may not persist without maintenance planning (consensus/clinical).

Monitoring & labs

During dosing sessions: monitor blood pressure, heart rate, and mental status (dissociation/sedation) (label/consensus).
When used repeatedly: track symptom response over time and ask about urinary symptoms and substance use risk (clinical).

Monitoring practices vary by protocol because psychiatric use is off-label; consensus statements emphasize structured follow-up.

Adverse effects

FDA boxed warnings

Common side effects (≥10%)

Dissociation / perceptual changes: Can occur during and shortly after administration; typically managed with a calm setting, reassurance, and time-limited observation (consensus/clinical).
Sedation and dizziness: Sedation and psychomotor impairment can persist for hours; counseling commonly includes safe transportation plans after dosing (consensus).
Blood pressure and heart rate increases: Transient elevations are common during dosing sessions; vital sign monitoring and cardiovascular screening are typical (label/consensus).
Nausea/vomiting: Nausea can occur during or after administration; supportive measures are commonly used (clinical).

Other notable effects

Misuse potential: ketamine is a controlled substance (Schedule III in the U.S.) and is associated with diversion and misuse (label/clinical).
Long-term high-frequency exposure is associated with urinary symptoms and cystitis; clinicians often review urinary symptoms when ketamine is used repeatedly (clinical).

Interactions

CNS depressants (alcohol, benzodiazepines, opioids) can compound sedation and impairment (label/clinical).
Strong CYP2B6 or CYP3A4 modulators may alter exposure; medication reconciliation is commonly done before sessions (label/clinical).
Sympathomimetic agents and stimulants can compound blood pressure and heart rate increases during sessions (clinical).

Other useful information

Ketamine’s depression use is off-label; FDA-approved intranasal esketamine is a separate product with a labeled REMS-based monitoring model (consensus/label).
Safety planning often includes transportation logistics and avoidance of high-risk activities (driving/operating machinery) until the effects have fully worn off (consensus).

References

Related hubs:SMI toolkit·Support resources