Dexamethasone

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: Dexamethasone

Examples of brand names: Fortecortin [DE]

ATC code: H02AB02

Main use (for orientation): Inflammation; oncology

Documented research summary

No isolated clinical dexamethasone–cannabinoid interaction established. Canine cells show enhanced immunosuppression with CBD/THC, while rat colon shows attenuation of CBD effects by dexamethasone; in shrews, no antiemetic THC–dexamethasone interaction in the experiment investigated. CBG after a dexamethasone atrophy model is preclinical subsequent treatment, not evidence of a simultaneous clinical interaction. Do not extrapolate CYP hypotheses and older animal isoenzyme findings to human AUC.

Uncertainties and limitations

Several relevant preclinical papers available only as abstracts; no treatment recommendations from animal/cell findings.

2026 CBG muscle paper uses a sequential experimental design; not a quantitative human risk.

Separately recorded findings

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

CBD – laboratory and animal studies

Finding ID: B0404

Type of result: Preclinical combination effect

Observation: Low dexamethasone concentrations suppressed IFN-γ more strongly in the presence of CBD, THC or their combination; similar changes in IFNG/TNFA mRNA.

Mechanism: Additive/enhanced immunosuppression in a cell model

Study type: Canine peripheral blood mononuclear cells in vitro

Context studied: Dog cells, not a human or in-vivo combination study.

Clinical interpretation: Interpret within the stated study context; no independent dosage or treatment recommendation.

Limitations and uncertainties: Abstract-based; no clinical dose reduction, infection rate or exposure magnitude established.

Original sources for this finding: Potential to use cannabinoids as adjunct therapy for dexamethasone: An in vitro study with canine peripheral blood mononuclear cells. [RMED38330886]

THC – laboratory and animal studies

Finding ID: B0405

Type of result: Preclinical combination effect

Observation: Low dexamethasone concentrations suppressed IFN-γ more strongly in the presence of CBD, THC or their combination; similar changes in IFNG/TNFA mRNA.

Mechanism: Additive/enhanced immunosuppression in a cell model

Study type: Canine peripheral blood mononuclear cells in vitro

Context studied: Dog cells, not a human or in-vivo combination study.

Clinical interpretation: Interpret within the stated study context; no independent dosage or treatment recommendation.

Limitations and uncertainties: Abstract-based; no clinical dose reduction, infection rate or exposure magnitude established.

Original sources for this finding: Potential to use cannabinoids as adjunct therapy for dexamethasone: An in vitro study with canine peripheral blood mononuclear cells. [RMED38330886]

CBD + THC – laboratory and animal studies

Finding ID: B0406

Type of result: Preclinical combination effect

Observation: Low dexamethasone concentrations suppressed IFN-γ more strongly in the presence of CBD, THC or their combination; similar changes in IFNG/TNFA mRNA.

Mechanism: Additive/enhanced immunosuppression in a cell model

Study type: Canine peripheral blood mononuclear cells in vitro

Context studied: Dog cells, not a human or in-vivo combination study.

Clinical interpretation: Interpret within the stated study context; no independent dosage or treatment recommendation.

Limitations and uncertainties: Abstract-based; no clinical dose reduction, infection rate or exposure magnitude established.

Original sources for this finding: Potential to use cannabinoids as adjunct therapy for dexamethasone: An in vitro study with canine peripheral blood mononuclear cells. [RMED38330886]

CBD-rich extract – laboratory and animal studies

Finding ID: B0407

Type of result: Preclinical signal of opposing effects

Observation: Dexamethasone attenuated CBD-induced inhibition of motility; combination response 67.6±16.8% versus CBD alone 26.5±8.6% of the acetylcholine control.

Mechanism: Pharmacodynamic opposing effect on acetylcholine-induced contraction

Study type: Isolated rat colon strips ex vivo

Context studied: CBD-rich extract 887.17 mg/g, other cannabinoids each <0.3 mg/g; nominal CBD 80 µM, dexamethasone 100 µM; n=5 replicates.

Clinical interpretation: Interpret within the stated study context; no independent dosage or treatment recommendation.

Limitations and uncertainties: Not pure CBD. Abstract/full-text contradiction concerning significance versus the acetylcholine control; direction versus CBD consistent. High concentrations, not a clinical motility prediction.

Original sources for this finding: Diclofenac and dexamethasone modulate the effect of cannabidiol on the rat colon motility ex vivo. [C_PR_38143819]

THC – laboratory and animal studies

Finding ID: B0408

Type of result: Preclinical null finding

Observation: THC showed no antiemetic interaction with dexamethasone in this model.

Mechanism: Antiemetic combination

Study type: Cisplatin emesis model in shrews

Context studied: THC 0–10 mg/kg and dexamethasone 0–20 mg/kg intraperitoneally; 60-minute observation after cisplatin.

Clinical interpretation: Interpret within the stated study context; no independent dosage or treatment recommendation.

Limitations and uncertainties: Not humans; not general safety. The tropisetron combination in the same paper showed a different effect.

Original sources for this finding: The antiemetic interaction of Delta9-tetrahydrocannabinol when combined with tropisetron or dexamethasone in the least shrew. [RMED18727934]

CBG – laboratory and animal studies

Finding ID: B0409

Type of result: Preclinical subsequent-treatment context, not a clinical interaction

Observation: CBG increased selected performance measures, particularly with training; muscle morphology and function responded differently.

Mechanism: Neuromuscular performance parameters after a glucocorticoid model

Study type: Dexamethasone-induced atrophy model in mice; subsequent intervention

Context studied: Dexamethasone for 12 days, followed by 4 weeks of training; CBG 10 mg/kg on training days.

Clinical interpretation: Interpret within the stated study context; no independent dosage or treatment recommendation.

Limitations and uncertainties: No evidence of a simultaneous drug interaction or human efficacy. Included as experimental context, not a protective recommendation.

Original sources for this finding: Cannabigerol Enhances Muscle Strength and Performance in Dexamethasone-Treated Mice. [RMED42871546]

References and access status

[RLABEL_D0036] HEMADY (DEXAMETHASONE) TABLET [EDENBRIDGE PHARMACEUTICALS LLC.]

Original source / bibliographic reference

Authors: Regulatory product information; respective marketing authorisation holder

Year: 2026

Source type: Product information / SmPC / US Prescribing Information

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

Bibliographic attribution or source identity cross-checked.

[RMED38330886] Potential to use cannabinoids as adjunct therapy for dexamethasone: An in vitro study with canine peripheral blood mononuclear cells.

Original source / bibliographic reference

Authors: Dixon S, Deb A, Archer T, Kaplan BLF.

Year: 2024

Source type: Original publication; see finding for study type

DOI: 10.1016/j.vetimm.2024.110727

PMID: 38330886

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

Bibliographic attribution or source identity cross-checked.

PubMed – bibliographic reference / abstract

[C_PR_38143819] Diclofenac and dexamethasone modulate the effect of cannabidiol on the rat colon motility ex vivo.

Original source / bibliographic reference

Authors: Chłopecka M, Kiraga Ł, Crowley K, Jank M, Latek U, Mendel M, Karlik W.

Year: 2023

Source type: Primary source, relevant full-text sections read

DOI: 10.2478/jvetres-2023-0029

PMID: 38143819

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.

PubMed – bibliographic reference / abstract

PubMed Central – archived text

DOI – publisher access (access restrictions may apply)

[RMED18727934] The antiemetic interaction of Delta9-tetrahydrocannabinol when combined with tropisetron or dexamethasone in the least shrew.

Original source / bibliographic reference

Authors: Wang Y, Ray AP, McClanahan BA, Darmani NA.

Year: 2009

Source type: Original publication; see finding for study type

DOI: 10.1016/j.pbb.2008.08.008

PMID: 18727934

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

Bibliographic attribution or source identity cross-checked.

PubMed – bibliographic reference / abstract

[RMED42871546] Cannabigerol Enhances Muscle Strength and Performance in Dexamethasone-Treated Mice.

Original source / bibliographic reference

Authors: Fabro IF, Nery T, Pinto de Araújo AP, Bastos Pereira AL, Felipetti FA, Aguiar AS.

Year: 2026

Source type: Original publication; see finding for study type

DOI: 10.1021/acsptsci.6c00187

PMID: 42871546

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.

PubMed – bibliographic reference / abstract

[RMED39754667] Cannabidiol (CBD) potentiates physiological and behavioral markers of hypothalamic-pituitary-adrenal (HPA) axis responsivity in female and male mice.

Original source / bibliographic reference

Authors: Jenkins BW, Spina HA, Nicholson K, Newman AEM, Khokhar JY.

Year: 2026

Source type: Original publication; see finding for study type

DOI: 10.1007/s00213-024-06737-z

PMID: 39754667

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

Bibliographic attribution or source identity cross-checked.

PubMed – bibliographic reference / abstract

[RMED1963558] Cannabinoid interactions with glucocorticoid receptors in rat hippocampus.

Original source / bibliographic reference

Authors: Eldridge JC, Landfield PW.

Year: 1990

Source type: Original publication; see finding for study type

DOI: 10.1016/0006-8993(90)90123-s

PMID: 1963558

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

Bibliographic attribution or source identity cross-checked.

PubMed – bibliographic reference / abstract

[RMED9763413] Major cytochrome P450 enzyme responsible for oxidation of secondary alcohols to the corresponding ketones in mouse hepatic microsomes. Oxidation of 7-hydroxy-delta8-tetrahydrocannabinol to 7-oxo-delta8-tetrahydrocannabinol.

Original source / bibliographic reference

Authors: Matsunaga T, Kishi N, Tanaka H, Watanabe K, Yoshimura H, Yamamoto I.

Year: 1998

Source type: Original publication; see finding for study type

PMID: 9763413

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.

PubMed – bibliographic reference / abstract

[RMED10706409] Characterization of microsomal alcohol oxygenase catalyzing the oxidation of 7-hydroxy-delta 8-tetrahydrocannabinol to 7-oxo-delta 8-tetrahydrocannabinol in rat liver.

Original source / bibliographic reference

Authors: Matsunaga T, Shibayama K, Higuchi S, Tanaka H, Watanabe K, Yamamoto I.

Year: 2000

Source type: Original publication; see finding for study type

DOI: 10.1248/bpb.23.43

PMID: 10706409

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

Bibliographic attribution or source identity cross-checked.

PubMed – bibliographic reference / abstract

[BMED2402224] Selective inactivation of mouse liver cytochrome P-450IIIA by cannabidiol.

Original source / bibliographic reference

Authors: Bornheim LM, Correia MA.

Year: 1990

Source type: Primary publication; abstract reviewed

DOI: 10.1016/s0026-895x(25)09483-0

PMID: 2402224

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.

PubMed – bibliographic reference / abstract

DOI – publisher access (access restrictions may apply)

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