Ketamine

For an informed discussion with your doctor or pharmacist. This information collection is not a clinically validated interaction checker. Missing data do not establish safety. Do not change or stop prescribed medicines on the basis of this information. The findings apply to the specific conditions studied; laboratory and animal studies cannot be directly extrapolated to humans.

Active substance: Ketamine

Examples of brand names: Ketanest [DE]

ATC code: N01AX03

Main use (for orientation): Anaesthesia; analgesia

Documented research summary

Hallak 2011 randomised crossover study in 10 healthy men: CBD 600 mg before ketamine (0.26 mg/kg bolus, then 0.25 mg/kg over 30 minutes) significantly enhanced the BPRS activation subscore; reduced depersonalisation was only a non-significant trend. Do not infer a measured pharmacokinetic interaction. Natural cannabis and anaesthesia: Ripperger 2023, retrospective 189 people (57 users) receiving four-drug anaesthesia, with more ketamine (46.1 versus 40.2 mg, p=0.01); Gangwani 2023, n=53, no adjusted difference in ketamine requirement (p=0.86); King 2021 small endoscopy cohort also without a difference. Solano 2021, n=86, prehospital intramuscular ketamine: marijuana-positive and negative patients had similar intubation rates; not randomised or a general safety guarantee. Shenasa 2023 preprint, retrospective mixed ketamine/esketamine group n=120 (40 with cannabis): no different depressive-symptom course, not a pharmacokinetic study; later publication PMID37579527 without an abstract available here. Animal data are context-dependent: CBD reduces ketamine-induced hyperlocomotion in some models but prolongs it in Brakatselos 2021; Frizza 1977 mice: THC prolongs ketamine anaesthesia, CBD and CBN predominantly inactive. Results prove neither human protection nor uniform toxic synergy.

Uncertainties and limitations

Very small direct human study, contradictory non-randomised anaesthesia observations and many preclinical models. For rare cannabinoids, only older CBN mouse data identified; no clinical pair study. Missing relevant case-report full texts limit detailed assessment without allowing a null conclusion.

Separately recorded findings

5 separately recorded findings. Each statement applies to its documented study context.

CBD, oral – clinically investigated

Finding ID: B0135

Type of result: Positive finding / indication

Observation: CBD significantly increased the BPRS activation factor with ketamine; reduced depersonalisation only a non-significant trend.

Mechanism: Pharmacodynamic psychological effect

Study type: Human experiment

Context studied: n=10 healthy men; CBD 600 mg before intravenous ketamine 0.26 mg/kg bolus plus 0.25 mg/kg over 30 minutes.

Clinical interpretation: Do not present CBD as general protection against ketamine adverse effects

Limitations and uncertainties: Small acute study; no ketamine pharmacokinetics or longer-term endpoints.

Original sources for this finding: The interplay of cannabinoid and NMDA glutamate receptor systems in humans: preliminary evidence of interactive effects of cannabidiol and ketamine in healthy human subjects. [CA_P_21062637]

Cannabis, observed use – clinical signals

Finding ID: B0136

Type of result: Contradictory findings

Observation: 2023 cohort n=189: ketamine requirement 46.1 versus 40.2 mg, p=0.01, users/non-users. Second cohort n=53: no adjusted difference, p=0.86.

Mechanism: Anaesthetic requirements within a multi-drug regimen; not isolated pharmacokinetics

Study type: Retrospective anaesthesia cohorts

Context studied: Outpatient oral surgery; combined midazolam/fentanyl/propofol/ketamine regimen. First cohort 57 users, second 27 THC-positive/26 negative.

Clinical interpretation: No fixed dose rule can be inferred

Limitations and uncertainties: Not randomised; urine positivity does not prove acute intoxication. Multiple medicines.

Original sources for this finding: Cannabis Users Require More Anesthetic Agents for General Anesthesia in Ambulatory Oral and Maxillofacial Surgery Procedures. [CA_P_37783364]; Is Recreational Marijuana Use Associated With Changes in the Vital Signs or Anesthetic Requirements During Intravenous Sedation? [CA_P_36746375]

Cannabis, toxicological detection – clinical signals

Finding ID: B0140

Type of result: No / minor effect under the conditions studied

Observation: Cannabis positivity not associated with a higher intubation frequency.

Mechanism: Observed intubation frequency after prehospital intramuscular ketamine

Study type: Emergency-medical-service/emergency-department cohort

Context studied: n=86; intramuscular ketamine for severe agitation in prehospital care.

Clinical interpretation: Limited to the emergency situation investigated

Limitations and uncertainties: Not randomised; a positive toxicology screen does not state dose. Do not attribute increased cocaine risk to cannabis.

Original sources for this finding: Prehospital Ketamine Administration for Excited Delirium with Illicit Substance Co-Ingestion and Subsequent Intubation in the Emergency Department. [CA_P_34551849]

CBD – laboratory and animal studies

Finding ID: B0150

Type of result: Mixed preclinical finding

Observation: CBD prolonged ketamine-induced hyperlocomotion in one rat study, while other protocols with repeated ketamine/sequential CBD reported improvement.

Mechanism: Preclinical behavioural modulation

Study type: Rat behavioural studies

Context studied: Acute pretreatment versus repeated/sequential regimens.

Clinical interpretation: No consistent clinical protective effect can be inferred

Limitations and uncertainties: Different exposure sequences/models; do not present as direct contradiction between identical experiments.

Original sources for this finding: Cannabidiol Modulates the Motor Profile and NMDA Receptor-related Alterations Induced by Ketamine. [CA_P_32950556]; CBD Effects on Motor Profile and Neurobiological Indices Related to Glutamatergic Function Induced by Repeated Ketamine Pre-Administration. [CA_P_34776964]

THC/CBN/CBD – laboratory and animal studies

Finding ID: B0151

Type of result: Differential preclinical finding

Observation: THC prolonged ketamine effects in a mouse experiment; CBN/CBD largely inactive in this historical regimen (CBD–pentobarbital exception is not a ketamine finding).

Mechanism: Preclinical anaesthesia duration

Study type: Historical mouse experiment

Context studied: THC 2.5–80 mg/kg; CBN/CBD 5–80 mg/kg; several anaesthetics investigated.

Clinical interpretation: Clinical significance unclear

Limitations and uncertainties: Not human or isolated enzyme evidence; do not extrapolate other anaesthetics to ketamine.

Original sources for this finding: The effect of delta 9-tetrahydrocannabinol, cannabidiol, and cannabinol on the anaesthesia induced by various anaesthetic agents in mice. [CA_P_414255]

References and access status

[CA_L_D0154] KETALAR (KETAMINE HYDROCHLORIDE) INJECTION [PAR HEALTH USA, LLC]

Original source / bibliographic reference

Authors: Par Health USA, LLC

Year: 2026

Source type: Current published human-use SPL / product information

Source access – 23 October 2026: Source destination was accessible when checked.

Bibliographic attribution or source identity cross-checked.

[CA_P_21062637] The interplay of cannabinoid and NMDA glutamate receptor systems in humans: preliminary evidence of interactive effects of cannabidiol and ketamine in healthy human subjects.

Original source / bibliographic reference

Authors: Hallak JE, Dursun SM, Bosi DC, de Macedo LR, Machado-de-Sousa JP, Abrão J, Crippa JA, McGuire P, Krystal JH, Baker GB, Zuardi AW.

Year: 2011

Source type: Randomized Controlled Trial; Research Support, U.S. Gov't, Non-P.H.S.; Journal Article; Research Support, N.I.H., Extramural

DOI: 10.1016/j.pnpbp.2010.11.002

PMID: 21062637

Source access – 23 October 2026: Source destination was accessible when checked.

Bibliographic attribution or source identity cross-checked.

DOI – publisher access (access restrictions may apply)

[CA_P_37783364] Cannabis Users Require More Anesthetic Agents for General Anesthesia in Ambulatory Oral and Maxillofacial Surgery Procedures.

Original source / bibliographic reference

Authors: Ripperger D, Atte A, Ritto F.

Year: 2023

Source type: Journal Article

DOI: 10.1016/j.joms.2023.09.008

PMID: 37783364

Source access – 23 October 2026: Direct retrieval could not be fully verified; availability remains unresolved.

Bibliographic attribution or source identity cross-checked.

DOI – publisher access (access restrictions may apply)

[CA_P_36746375] Is Recreational Marijuana Use Associated With Changes in the Vital Signs or Anesthetic Requirements During Intravenous Sedation?

Original source / bibliographic reference

Authors: Gangwani P, Lillian D, Dobbins J, Feng C, Vorrasi J, Kolokythas A.

Year: 2023

Source type: Journal Article

DOI: 10.1016/j.joms.2023.01.007

PMID: 36746375

Source access – 23 October 2026: Source destination was accessible when checked.

Bibliographic attribution or source identity cross-checked.

DOI – publisher access (access restrictions may apply)

[CA_P_34042571] Anesthesia for Patients Who Self-Report Cannabis (Marijuana) Use Before Esophagogastroduodenoscopy: A Retrospective Review.

Original source / bibliographic reference

Authors: King DD, Stewart SA, Collins-Yoder A, Fleckner T, Price LL.

Year: 2021

Source type: research-article; Journal Article

PMID: 34042571

Source access – 23 October 2026: Direct retrieval could not be fully verified; availability remains unresolved.

Bibliographic attribution or source identity cross-checked.

Unresolved access questions / further review: No new complete methodological assessment; original direct PubMed retrieval incomplete.

PubMed Central – freely accessible full text

[CA_P_34551849] Prehospital Ketamine Administration for Excited Delirium with Illicit Substance Co-Ingestion and Subsequent Intubation in the Emergency Department.

Original source / bibliographic reference

Authors: Solano JJ, Clayton LM, Parks DJ, Polley SE, Hughes PG, Hennekens CH, Shih RD, Alter SM.

Year: 2021

Source type: research-article; Journal Article

DOI: 10.1017/s1049023x21000935

PMID: 34551849

Source access – 23 October 2026: Direct retrieval could not be fully verified; availability remains unresolved.

Bibliographic attribution or source identity cross-checked.

DOI – publisher access (access restrictions may apply)

PubMed Central – full-text access according to the literature database – Archive attribution confirmed by Europe PMC metadata. Direct retrieval was not fully verified here; access may require a browser check.

Europe PMC – full-text access according to the literature database – Listed as freely available HTML full text in the official Europe PMC metadata. Direct retrieval was not fully verified here.

[CA_P_41850603] Cannabidiol Mitigates Ketamine-Induced Hyperlocomotion Via Allosteric Potentiation of Ventral Tegmental Glycine Receptor α1 Signaling.

Original source / bibliographic reference

Authors: Wang X, Xia J, Luo H, Mao H, Wang D, Jin J, Xiong W.

Year: 2026

Source type: Journal Article

DOI: 10.1016/j.biopsych.2026.03.992

PMID: 41850603

Source access – 23 October 2026: Direct retrieval could not be fully verified; availability remains unresolved.

Bibliographic attribution or source identity cross-checked.

DOI – publisher access (access restrictions may apply)

[CA_P_41453846] Effects of ketamine enantiomers on morphine and THC subjective effects in rats.

Original source / bibliographic reference

Authors: Malikowska-Racia N, Golebiowska J, Starowicz K, Zajdel P, Bisaga A, Popik P.

Year: 2025

Source type: Journal Article

DOI: 10.1177/02698811251406839

PMID: 41453846

Source access – 23 October 2026: Direct retrieval could not be fully verified; availability remains unresolved.

Bibliographic attribution or source identity cross-checked.

DOI – publisher access (access restrictions may apply)

[CA_P_414255] The effect of delta 9-tetrahydrocannabinol, cannabidiol, and cannabinol on the anaesthesia induced by various anaesthetic agents in mice.

Original source / bibliographic reference

Authors: Frizza J, Chesher GB, Jackson DM, Malor R, Starmer GA.

Year: 1977

Source type: Journal Article

DOI: 10.1007/bf00432824

PMID: 414255

Source access – 23 October 2026: Direct retrieval could not be fully verified; availability remains unresolved.

Bibliographic attribution or source identity cross-checked.

DOI – publisher access (access restrictions may apply)

[CA_P_32950556] Cannabidiol Modulates the Motor Profile and NMDA Receptor-related Alterations Induced by Ketamine.

Original source / bibliographic reference

Authors: Brakatselos C, Delis F, Asprogerakas MZ, Lekkas P, Tseti I, Tzimas PS, Petrakis EA, Halabalaki M, Skaltsounis LA, Antoniou K.

Year: 2021

Source type: Research Support, Non-U.S. Gov't; Journal Article

DOI: 10.1016/j.neuroscience.2020.09.029

PMID: 32950556

Source access – 23 October 2026: Source destination was accessible when checked.

Bibliographic attribution or source identity cross-checked.

DOI – publisher access (access restrictions may apply)

[CA_P_34776964] CBD Effects on Motor Profile and Neurobiological Indices Related to Glutamatergic Function Induced by Repeated Ketamine Pre-Administration.

Original source / bibliographic reference

Authors: Poulia N, Delis F, Brakatselos C, Ntoulas G, Asprogerakas MZ, Antoniou K.

Year: 2021

Source type: research-article; Journal Article

DOI: 10.3389/fphar.2021.746935

PMID: 34776964

Source access – 23 October 2026: Automated direct retrieval was restricted; this does not establish that the link is broken.

Bibliographic attribution or source identity cross-checked.

DOI – publisher access (access restrictions may apply)

PubMed Central – full-text access according to the literature database – Archive attribution confirmed by Europe PMC metadata. Direct retrieval was not fully verified here; access may require a browser check.

Europe PMC – full-text access according to the literature database – Listed as freely available HTML full text in the official Europe PMC metadata. Direct retrieval was not fully verified here.

[CA_P_31823199] Cannabidiol Improves Cognitive Impairment and Reverses Cortical Transcriptional Changes Induced by Ketamine, in Schizophrenia-Like Model in Rats.

Original source / bibliographic reference

Authors: Kozela E, Kozela E, Krawczyk M, Kos T, Juknat A, Vogel Z, Popik P.

Year: 2020

Source type: Journal Article

DOI: 10.1007/s12035-019-01831-2

PMID: 31823199

Source access – 23 October 2026: Direct retrieval could not be fully verified; availability remains unresolved.

Bibliographic attribution or source identity cross-checked.

DOI – publisher access (access restrictions may apply)

[CA_P_15840405] Cannabidiol inhibits the hyperlocomotion induced by psychotomimetic drugs in mice.

Original source / bibliographic reference

Authors: Moreira FA, Guimarães FS.

Year: 2005

Source type: Comparative Study; Research Support, Non-U.S. Gov't; Journal Article

DOI: 10.1016/j.ejphar.2005.02.040

PMID: 15840405

Source access – 23 October 2026: Automated direct retrieval was restricted; this does not establish that the link is broken.

Bibliographic attribution or source identity cross-checked.

DOI – publisher access (access restrictions may apply)

[CA_P_39242923] Multi-level therapeutic actions of cannabidiol in ketamine-induced schizophrenia psychopathology in male rats.

Original source / bibliographic reference

Authors: Brakatselos C, Polissidis A, Ntoulas G, Asprogerakas MZ, Tsarna O, Vamvaka-Iakovou A, Nakas G, Delis A, Tzimas P, Skaltsounis L, Silva J, Delis F, Oliveira JF, Sotiropoulos I, Antoniou K.

Year: 2024

Source type: Research Support, Non-U.S. Gov't; research-article; Journal Article; Research Support, N.I.H., Extramural

DOI: 10.1038/s41386-024-01977-1

PMID: 39242923

Source access – 23 October 2026: Direct retrieval could not be fully verified; availability remains unresolved.

Bibliographic attribution or source identity cross-checked.

DOI – publisher access (access restrictions may apply)

PubMed Central – full-text access according to the literature database – Archive attribution confirmed by Europe PMC metadata. Direct retrieval was not fully verified here; access may require a browser check.

Europe PMC – full-text access according to the literature database – Listed as freely available HTML full text in the official Europe PMC metadata. Direct retrieval was not fully verified here.

[CA_P_40132281] Cannabidiol reverses myeloperoxidase hyperactivity in the prefrontal cortex and striatum, and reduces protein carbonyls in the hippocampus in a ketamine-induced schizophrenia rat model.

Original source / bibliographic reference

Authors: de Almeida Queiroz S, de Novais Junior LR, de Carvalho ABP, da Silva TV, de Souza Ramos S, Meneguzzo V, Mathias K, Tiscoski ADB, Piacentini N, de Souza Goldim MP, Iser BPM, Petronilho F, Inserra A, de Bitencourt RM.

Year: 2025

Source type: Journal Article

DOI: 10.1016/j.schres.2025.03.031

PMID: 40132281

Source access – 23 October 2026: Direct retrieval could not be fully verified; availability remains unresolved.

Bibliographic attribution or source identity cross-checked.

DOI – publisher access (access restrictions may apply)

[CA_P_40886890] Prophylactic efficacy of cannabidiol and sodium nitroprusside in a ketamine model of schizophrenia: sex-dependent effects on positive-like and cognitive impairments.

Original source / bibliographic reference

Authors: Prado DBA, Rossignoli MT, Ruggiero RN, Santos JEP, Leite JP, Dursun SM, Dursun LH, Zuardi AW, Dos Santos RG, Abilio VC, Abrão J, Crippa JA, Avelar GG, Hallak JEC, Dias ICS.

Year: 2026

Source type: Journal Article

DOI: 10.47626/1516-4446-2025-4301

PMID: 40886890

Source access – 23 October 2026: Source destination was accessible when checked.

Bibliographic attribution or source identity cross-checked.

DOI – publisher access (access restrictions may apply)

[CA_P_41369966] Unraveling Cannabidiol's Dual Modulatory Role in Schizophrenia: Network Pharmacology and In Vivo Validation of Neuroinflammatory and Behavioral Modulation.

Original source / bibliographic reference

Authors: Wei Y, Liu X, Lin S, Jia Z, Liu L, Wang B, Liao L, Mei X.

Year: 2025

Source type: research-article; Journal Article

DOI: 10.1007/s12035-025-05608-8

PMID: 41369966

Source access – 23 October 2026: Automated direct retrieval was restricted; this does not establish that the link is broken.

Bibliographic attribution or source identity cross-checked.

DOI – publisher access (access restrictions may apply)

PubMed Central – full-text access according to the literature database – Archive attribution confirmed by Europe PMC metadata. Direct retrieval was not fully verified here; access may require a browser check.

Europe PMC – full-text access according to the literature database – Listed as freely available HTML full text in the official Europe PMC metadata. Direct retrieval was not fully verified here.

[CA_P_38087263] Commonly used anesthetics modify alcohol and (-)-trans-delta9-tetrahydrocannabinol in vivo effects on rat cerebral arterioles.

Original source / bibliographic reference

Authors: Mysiewicz S, Hibl B, Dopico A, Bukiya A.

Year: 2023

Source type: research-article; Journal Article; Research Support, N.I.H., Extramural

DOI: 10.1186/s12871-023-02320-9

PMID: 38087263

Source access – 23 October 2026: Direct retrieval could not be fully verified; availability remains unresolved.

Bibliographic attribution or source identity cross-checked.

DOI – publisher access (access restrictions may apply)

PubMed Central – full-text access according to the literature database – Archive attribution confirmed by Europe PMC metadata. Direct retrieval was not fully verified here; access may require a browser check.

Europe PMC – full-text access according to the literature database – Listed as freely available HTML full text in the official Europe PMC metadata. Direct retrieval was not fully verified here.

[CA_P_34157363] Co-administration of cannabidiol and ketamine induces antidepressant-like effects devoid of hyperlocomotor side-effects.

Original source / bibliographic reference

Authors: Sartim AG, Marques J, Silveira KM, Gobira PH, Guimarães FS, Wegener G, Joca SR.

Year: 2021

Source type: Research Support, Non-U.S. Gov't; Journal Article

DOI: 10.1016/j.neuropharm.2021.108679

PMID: 34157363

Source access – 23 October 2026: Direct retrieval could not be fully verified; availability remains unresolved.

Bibliographic attribution or source identity cross-checked.

DOI – publisher access (access restrictions may apply)

[CA_P_19887017] Interaction of drugs of abuse and maintenance treatments with human P-glycoprotein (ABCB1) and breast cancer resistance protein (ABCG2).

Original source / bibliographic reference

Authors: Tournier N, Chevillard L, Megarbane B, Pirnay S, Scherrmann JM, Declèves X.

Year: 2010

Source type: Journal Article

DOI: 10.1017/s1461145709990848

PMID: 19887017

Source access – 23 October 2026: Source destination was accessible when checked.

Bibliographic attribution or source identity cross-checked.

DOI – publisher access (access restrictions may apply)

[CA_P_PPR683577] Effects of cannabis use on antidepressant treatment response to repetitive transcranial magnetic stimulation and ketamine

Original source / bibliographic reference

Authors: Shenasa MA, Afshar HT, Miller EA, Ellerman-Tayag E, Mishra J, Ramanathan D.

Year: 2023

Source type: Preprint

DOI: 10.1101/2023.06.28.23291446

Source access – 23 October 2026: Automated direct retrieval was restricted; this does not establish that the link is broken.

Bibliographic attribution or source identity cross-checked.

Unresolved access questions / further review: Do not count as an additional independent study. medRxiv Connect names later journal publication DOI 10.1016/j.euroneuro.2023.07.013; content comparison between versions not performed here.

medRxiv – preprint full text (non-peer-reviewed version) – Preprint version; direct retrieval may be restricted. No new complete content assessment.

[CA_P_PPR1230589] (S)-ketamine augments behavioral and physiological responses to Δ9-tetrahydrocannabinol

Original source / bibliographic reference

Authors: Keimpema E, Vigl V, Torgasheva N, Romanov RA, Kasper S, Harkany T.

Year: 2025

Source type: Preprint

DOI: 10.64898/2025.12.18.695060

Source access – 23 October 2026: Source destination was accessible when checked.

Bibliographic attribution or source identity cross-checked.

Research as of 23 October 2026. Not all original full texts could be reviewed in full. Source accessibility and the strength of scientific evidence must be assessed separately. An accessible link does not establish medical approval; a bibliographic record with an abstract does not replace the original full text.

Drug search and explanation of the evidence · Guide: cannabinoids and medicines · Author and responsibility