Esketamine Research Reference

Catalog classification, reference sizes, lab math links, and source-backed data. Educational use only — not medical advice.

Researched for: PepTools vendor-neutral scientific reference catalog

NMDA receptor antagonist; antidepressant; dissociative anesthetic compound Reference needs_revision Best effort · source review pending

Also known as: S-ketamine, (S)-ketamine, l-ketamine, (-)-ketamine, S-(-)-ketamine, esketamine hydrochloride

Open in Calculator ← Compound Index All Tools

Best-effort research profile: this record has not passed full two-source scientific verification. Descriptive fields, research protocols, storage/handling notes, and interaction guidance below are shown with their evidence labels, but calculator presets and exact dosing math remain hidden until the record is verified or reaches Community-Supported status.

Quick Facts

Reference Sizes

Not standardized / source review pending

Storage

For the FDA-labeled nasal-spray product: store at 20–25 °C (68–77 °F); excursions are permitted from 15–30 °C (59–86 °F). These conditions apply to the packaged product and should not be generalized to unspecified bulk compound.

Solubility

Esketamine hydrochloride is freely soluble in water and methanol and soluble in ethanol. The approved nasal-spray product is a clear, colorless aqueous solution.

Best-Effort Research Profile

Esketamine is a chiral arylcyclohexylamine related to ketamine. The active pharmaceutical form used in the approved nasal-spray product is esketamine hydrochloride. Its pharmacologic activity includes antagonism of the NMDA ionotropic glutamate receptor; the precise mechanism underlying antidepressant effects is not established. Esketamine is classified in the WHO ATC system under N06AX27 (other antidepressants) and is also associated with the anesthetic classification N01AX14.

Source review pending. This descriptive profile is shown from the available source material as a best-effort educational reference. It has not passed the full verification bar and is not a dosing instruction, medical claim, or treatment recommendation.

Research Profile

Half-Life

Following intranasal administration, the mean terminal plasma half-life of esketamine is approximately 7–12 hours. The major metabolite noresketamine has a mean terminal half-life of approximately 8 hours.

Onset

Maximum plasma concentration is reached approximately 20–40 minutes after the last nasal spray of a treatment session. In clinical studies, treatment-response differences were observed at approximately 24 hours in the studied indications; this is not equivalent to a universal pharmacodynamic onset.

Administration Routes (Research)

intranasal

Reported Research Effects

NMDA receptor antagonism
Antidepressant activity in approved clinical use
Dissociative and central-nervous-system depressant effects
Sedation, dizziness, and transient cognitive or psychomotor impairment are described in product labeling
Transient increases in blood pressure and heart rate are described in product labeling

Reflects preclinical/research literature context only. Not a medical claim, dosing instruction, or treatment recommendation.

Research Notes

Esketamine is the S-enantiomer of racemic ketamine. FDA labeling reports approximately 48% mean absolute bioavailability after nasal-spray administration, plasma Tmax of 20–40 minutes, protein binding of approximately 43–45%, and metabolism primarily to noresketamine through CYP2B6 and CYP3A4, with lesser contributions from CYP2C9 and CYP2C19. The approved nasal-spray device delivers 28 mg esketamine base equivalent per device. Evidence-backed clinical regimens and doses are product- and indication-specific and are not generalized here as research-use instructions.

Supplementary research context only. Not medical advice or a treatment recommendation.

Registry Identifiers

PubChem CID 182137; esketamine molecular formula C13H16ClNO; molecular weight 237.72 g/mol; esketamine hydrochloride molecular formula C13H16ClNO·HCl; molecular weight 274.2 g/mol; CAS RN esketamine 33643-46-8; CAS RN esketamine hydrochloride 33643-47-9; InChIKey YQEZLKZALYSWHR-ZDUSSCGKSA-N; UNII 50LFG02TXD; ATC N06AX27 and N01AX14.

Source-Backed Observations

Esketamine hydrochloride is described in the FDA labeling as a white or almost white crystalline powder, freely soluble in water and methanol, and soluble in ethanol. The FDA-labeled nasal-spray product is an aqueous solution intended for nasal administration. In the United States, ketamine is listed by DEA as a Schedule III example; controlled-substance classification can depend on the specific substance, salt, isomer, and applicable jurisdiction.

Reflects published research. Educational reference — not a recommendation for use.

Sources Under Review

SPRAVATO (esketamine hydrochloride) FDA Prescribing Information, 2025 revision
https://www.accessdata.fda.gov/drugsatfda_docs/label/2025/211243s016lbl.pdf (accessed 2026-09-30)

Esketamine, PubChem Compound Summary, CID 182137
https://pubchem.ncbi.nlm.nih.gov/compound/182137 (accessed 2026-09-30)

Spravato: European Public Assessment Report
https://www.ema.europa.eu/en/medicines/human/EPAR/spravato (accessed 2026-09-30)

Drug Scheduling
https://www.dea.gov/drug-information/drug-scheduling (accessed 2026-09-30)

Suggest a community source

Found a relevant Reddit or forum thread about this compound? Suggest it below. Every suggestion is reviewed by an editor before it appears -- nothing is published automatically.

Related Research Tools

Reconstitution CalculatorConcentration, draw volume, per-unit amounts Unit Convertermg, mcg, mL, units conversion Compound CompareSide-by-side comparison tool Cost CalculatorCost per mg, mcg, per-draw

Research Use Only. All content is for educational and research reference only. Not medical advice, a treatment recommendation, or guidance on human use. Compounds are not FDA-approved drugs unless specifically noted.