Mirtazapine

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: Mirtazapine

Examples of brand names: Remergil [DE]

ATC code: N06AX11

Main use (for orientation): Depression

Documented research summary

CBD had only a small effect on mirtazapine metabolism in vitro in 2021; this does not establish clinical safety. A CBD add-on case in a 20-year-old reported improvement without controlled causal assessment. Two retrospective cases with THC-rich cannabis flowers and mirtazapine describe pancreatitis/hyperhidrosis or arthralgia with additional co-medication; the claimed CYP mechanism was not proven by concentration measurements. The small human cannabis-withdrawal laboratory study showed better sleep/appetite with mirtazapine but no reduction in relapse; not a pair pharmacokinetic study.

Uncertainties and limitations

Uncontrolled case reports and selected reporting data provide neither incidence nor established pharmacokinetic causality.

Do not equate cannabis flowers containing 18–22% THC/≤1% CBD with isolated THC or CBD.

Do not infer general safety from a limited in-vitro null finding.

Separately recorded findings

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

CBD – laboratory and animal studies

Finding ID: B0414

Type of result: Limited in-vitro null/minimal effect

Observation: No CYP2D6 inhibition of mirtazapine metabolism in the recombinant enzyme experiment; weak CYP3A4 inhibition with Ki >10 µM. Not clinical mirtazapine safety evidence.

Mechanism: Investigation of CBD-related inhibition of metabolism

Study type: In-vitro metabolism study

Context studied: The original study also includes a human arm involving citalopram/escitalopram, not this active substance.

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

Limitations and uncertainties: The authors' full-text version (tables and text presented in HTML) was reviewed. The human arm of this study concerns only the mixed citalopram/escitalopram series. No clinical safety or efficacy conclusion for this active substance; time-dependent inhibition and other mechanisms were not comprehensively investigated.

Original sources for this finding: Citalopram and Cannabidiol: In Vitro and In Vivo Evidence of Pharmacokinetic Interactions Relevant to the Treatment of Anxiety Disorders in Young People [CL10]

CBD – clinical signals

Finding ID: B0415

Type of result: Uncontrolled co-exposure context

Observation: Symptom improvements reported after CBD was added to existing treatment.

Mechanism: CBD as adjunctive treatment; no demonstrated pharmacokinetic mechanism

Study type: Single uncontrolled treatment case

Context studied: 20-year-old man, depression/anxiety and attenuated psychotic symptoms; mirtazapine and psychotherapy; CBD 200–800 mg/day over six months.

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

Limitations and uncertainties: Abstract only; no controlled efficacy or safety assessment and no drug concentrations. Do not use as an adjunctive-treatment recommendation.

Original sources for this finding: Treatment of social anxiety disorder and attenuated psychotic symptoms with cannabidiol. [RMED33028567]

THC-rich cannabis flowers; small CBD content – clinical signals

Finding ID: B0416

Type of result: Confounded clinical warning signals

Observation: Pancreatitis/hyperhidrosis or arthralgia reported with mirtazapine and cannabis flowers.

Mechanism: Authors' suspected pharmacokinetic/pharmacodynamic interaction; not measured

Study type: Two cases from a retrospective adverse-effect analysis

Context studied: Mirtazapine 45 or 30 mg/day; flowers containing THC 22%/CBD 1% or THC 18%/CBD ≤1%; additional medicines, including opioids/gabapentinoids.

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

Limitations and uncertainties: Selected reports without a denominator, control group or pharmacokinetics. THC percentage is not daily consumed dose. Alternative causes and co-medications prevent established pair causality.

Original sources for this finding: Green rush and red warnings: Retrospective chart review of adverse events of interactions between cannabinoids and psychotropic drugs. [CA_P_39502532]

Smoked cannabis; THC-containing – clinical signals

Finding ID: B0417

Type of result: Controlled treatment context without an established interaction mechanism

Observation: Mirtazapine improved sleep during abstinence and increased food intake; other withdrawal symptoms and relapse in the laboratory model were not reduced.

Mechanism: Pharmacodynamic treatment context, not pair pharmacokinetics

Study type: Small placebo-controlled human withdrawal/relapse laboratory study

Context studied: Mirtazapine arm n=11, 30 mg/day; regular cannabis users, controlled smoking/abstinence/relapse phases.

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

Limitations and uncertainties: Abstract-based. No claim that the combination is generally safe or approved for withdrawal treatment. Baclofen was a separate study arm.

Original sources for this finding: Effects of baclofen and mirtazapine on a laboratory model of marijuana withdrawal and relapse. [CA_P_20521030]

References and access status

[RLABEL_D0109] MIRTAZAPINE (MIRTAZAPINE) TABLET, FILM COATED [CAMBER PHARMACEUTICALS, INC.]

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.

[CA_P_39502532] Green rush and red warnings: Retrospective chart review of adverse events of interactions between cannabinoids and psychotropic drugs.

Original source / bibliographic reference

Authors: Chrobak AA, Woroń J, Siwek M.

Year: 2024

Source type: research-article; Journal Article

DOI: 10.3389/fphar.2024.1500312

PMID: 39502532

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.

[CL10] Citalopram and Cannabidiol: In Vitro and In Vivo Evidence of Pharmacokinetic Interactions Relevant to the Treatment of Anxiety Disorders in Young People

Original source / bibliographic reference

Authors: Anderson LL; Doohan PT; Oldfield L; Kevin RC; Arnold JC; Berger M; Amminger GP; McGregor IS

Year: 2021

Source type: In-vitro study plus a small accompanying clinical investigation

DOI: 10.1097/JCP.0000000000001427

PMID: 34121064

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)

[RMED33028567] Treatment of social anxiety disorder and attenuated psychotic symptoms with cannabidiol.

Original source / bibliographic reference

Authors: Berger M, Li E, Amminger GP.

Year: 2020

Source type: Original publication; see finding for study type

DOI: 10.1136/bcr-2020-235307

PMID: 33028567

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 – 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_20521030] Effects of baclofen and mirtazapine on a laboratory model of marijuana withdrawal and relapse.

Original source / bibliographic reference

Authors: Haney M, Hart CL, Vosburg SK, Comer SD, Reed SC, Cooper ZD, Foltin RW.

Year: 2010

Source type: Primary / secondary publication; design and use described in the individual review

DOI: 10.1007/s00213-010-1888-6

PMID: 20521030

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.

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