Bergamaschi MM, Karschner EL, Goodwin RS, Scheidweiler KB, Hirvonen J, Queiroz RHC, et al. Impact of prolonged cannabinoid excretion in chronic daily cannabis smokers’ blood on per se drugged driving laws. Clin Chem. 2013;59(3):519–26. https://doi.org/10.1373/clinchem.2012.195503.
Hayakawa K, Mishima K, Hazekawa M, Sano K, Irie K, Orito K, et al. Cannabidiol potentiates pharmacological effects of Δ9-tetrahydrocannabinol via CB1 receptor-dependent mechanism. Brain Res. 2008;1188:157–64. https://doi.org/10.1016/j.brainres.2007.09.090.
Hunt GE, Siegfried N, Morley K, Brooke-Sumner C, Cleary M. Psychosocial interventions for people with both severe mental illness and substance misuse. Cochrane Database Syst Rev. 2019;12(12):CD001088. https://doi.org/10.1002/14651858.CD001088.pub4.
The profile of CBD allows for a new and revolutionary paradigm for treating dual diagnosis patients with a potentially substantial impact on the course of illness and the level of functioning. Consequently, CBD has the potential to counteract the transition of acute psychosis to more chronic conditions. The results may have a possible major advantage for current and future patients.
Availability of data and materials
Serious Adverse Event
Use of self-administered CBD products during the trial
Schubart CD, Sommer IEC, Fusar-Poli P, de Witte L, Kahn RS, Boks MPM. Cannabidiol as a potential treatment for psychosis. Eur Neuropsychopharmacol. 2014;24(1):51–64. https://doi.org/10.1016/j.euroneuro.2013.11.002.
Sample size estimation
No other psychotropic medication can be added during the trial except benzodiazepines at a maximum dose equivalent to lorazepam 6 mg daily.
The Cannabis sativa plant contains approximately 100 active compounds (phytocannabinoids). The two major active components are the psychoactive Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD) .
Robinson SM, Sobell LC, Sobell MB, Leo GI (2014) Reliability of the Timeline Followback for cocaine, cannabis, and cigarette use. Psychol Addict Behav 28:154–162. https://doi.org/10.1037/a0030992
Schoeler T, Monk A, Sami MB et al (2016) Continued versus discontinued cannabis use in patients with psychosis: a systematic review and meta-analysis. Lancet Psychiatry 3:215–225. https://doi.org/10.1016/S2215-0366(15)00363-6
Davies C, Cipriani A, Ioannidis JPA et al (2018a) Lack of evidence to favor specific preventive interventions in psychosis: a network meta-analysis. World Psychiatry 17:196–209. https://doi.org/10.1002/wps.20526
Boggs DL, Surti T, Gupta A et al (2018) The effects of cannabidiol (CBD) on cognition and symptoms in outpatients with chronic schizophrenia a randomized placebo controlled trial. Psychopharmacology 235:1923–1932. https://doi.org/10.1007/s00213-018-4885-9
Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.
Freeman TP, Hindocha C, Baio G et al (2020) Cannabidiol for the treatment of cannabis use disorder: a phase 2a, double-blind, placebo-controlled, randomised, adaptive Bayesian trial. Lancet Psychiatry 7:865–874. https://doi.org/10.1016/S2215-0366(20)30290-X
Conflict of interest
Valmaggia LR, Day FL, Jones C et al (2014) Cannabis use and transition to psychosis in people at ultra-high risk. Psychol Med 44:2503–2512. https://doi.org/10.1017/S0033291714000117
Huhn M, Nikolakopoulou A, Schneider-Thoma J et al (2019) Comparative efficacy and tolerability of 32 oral antipsychotics for the acute treatment of adults with multi-episode schizophrenia: a systematic review and network meta-analysis. Lancet 394:939–951. https://doi.org/10.1016/S0140-6736(19)31135-3
They concluded: “The main group effects in the discontinuous multilevel model were higher subjective well-being and less overall antipsychotic medication use throughout the acute therapy for the CBD-group. These results may suggest an antipsychotic medication sparing effect of CBD-cigarettes as adjunctive therapy in acutely psychotic patients. … However, future studies with more rigorous study designs and larger samples are needed.”
Investigators reported that both CBD and placebo were associated with similar reductions in psychotic symptoms and depression, but that those participants who consumed CBD cigarettes used fewer antipsychotic medication during treatment. Conversely, those in the placebo group increased their use of prescription medications.
An international team of researchers from Canada, Switzerland, and Germany assessed the use of CBD cigarettes versus placebo in a cohort of acutely psychotic patients with schizophrenia or other psychotic disorders. Patients received either CBD or a placebo daily for 28 days in addition to their standard treatments.
Basel, Switzerland: The adjunctive use of CBD is associated with a reduction in patients’ use of antipsychotic medicines, according to placebo-controlled trial data published in the journal Frontiers in Psychiatry.
CBD administration is established to have anxiolytic and antipsychotic effects in human subjects, and its use is associated with changes in brain activity that may lower some people’s risk of a psychotic episode. Previously published clinical trial data indicates that the daily administration of high doses of CBD (1,000mg) reduces psychotic symptoms in patients with schizophrenia in a manner that is superior to the prescription antipsychotic agent amisulpride.
Full text of the study, “Cannabidiol cigarettes as adjunctive treatment for psychotic disorders – A randomized, open-label pilot study,” appears in Frontiers in Psychiatry.