Research study · Journal of Clinical Oncology · 2024
Oral Cannabis Extract for Chemotherapy-Induced Nausea and Vomiting: A Randomized, Placebo-Controlled Phase II/III Trial
Verified on PubMed Randomized controlled trial
A 2024 randomized controlled trial in Journal of Clinical Oncology tested cannabis in nausea. Adding a THC:CBD capsule raised the proportion of people who got through five days with no vomiting and no rescue medication from 8% to 24%. This is one of the clearer signals we have.
In plain language
Study overview
A randomised trial in adults who were still being sick during chemotherapy despite already taking the standard anti-sickness medicines.
Findings
Adding a THC:CBD capsule raised the proportion of people who got through five days with no vomiting and no rescue medication from 8% to 24%. Sedation, dizziness and short-lived anxiety were more common.
The deeper readScientific analysis
147 participants received either capsules containing 2.5 mg THC plus 2.5 mg CBD or matching placebo, three times daily from the day before chemotherapy through day 5, on top of guideline-consistent antiemetic prophylaxis. That background regimen was substantial: 97% received a corticosteroid and a 5-HT3 antagonist, 80% an NK-1 antagonist.
The primary endpoint was a complete response across hours 0-120 - no vomiting or retching and no rescue medication. THC:CBD improved that from 8% to 24%, an absolute difference of 16% (95% CI, 4 to 28; P = .01). Effects pointed the same way for significant nausea, rescue medication use, daily vomits, and the nausea scale of the Functional Living Index-Emesis.
The trade-off is explicit in the data. Sedation was reported by 18% versus 7%, dizziness 10% versus 0%, and transient anxiety 4% versus 1%. No serious adverse events were attributed to the study drug. The trial recruited 147 of a planned 250 participants, so it is smaller than intended.
The paper
Citation
Grimison P, Mersiades A, Kirby A, Tognela A, Olver I, Morton RL, et al. Oral Cannabis Extract for Chemotherapy-Induced Nausea and Vomiting: A Randomized, Placebo-Controlled Phase II/III Trial. Journal of Clinical Oncology (2024). PubMed 39151115 · DOI
Read the abstract as published
PURPOSE: The aim of this randomized, placebo-controlled, two-stage, phase II/III trial was to determine the efficacy of an oral cannabis extract in adults with refractory nausea and/or vomiting during moderately or highly emetogenic, intravenous chemotherapy despite guideline-consistent antiemetic prophylaxis. Here, we report results of the prespecified combined analysis including the initial phase II and subsequent phase III components.
PATIENTS AND METHODS: Study treatment consisted of oral capsules containing either tetrahydrocannabinol 2.5 mg plus cannabidiol 2.5 mg capsules (THC:CBD) or matching placebo, taken three times a day from days -1 to 5, in addition to guideline-consistent antiemetics. The primary measure of effect was the difference in the proportions of participants with no vomiting or retching and no use of rescue medications (a complete response) during hours 0-120 after the first cycle of chemotherapy on study (cycle A).
RESULTS: We recruited 147 evaluable of a planned 250 participants from 2016 to 2022. Background antiemetic prophylaxis included a corticosteroid and 5-hydroxytryptamine antagonist in 97%, a neurokinin-1 antagonist in 80%, and olanzapine in 10%. THC:CBD compared with placebo improved the complete response rate from 8% to 24% (absolute difference 16%, 95% CI, 4 to 28, P = .01), with similar effects for absence of significant nausea, use of rescue medications, daily vomits, and the nausea scale on the Functional Living Index-Emesis quality-of-life questionnaire. More frequent bothersome adverse events of special interest included sedation (18% v 7%), dizziness (10% v 0%), and transient anxiety (4% v 1%). There were no serious adverse events attributed to THC:CBD.
CONCLUSION: THC:CBD is an effective adjunct for chemotherapy-induced nausea and vomiting despite standard antiemetic prophylaxis, but was associated with additional adverse events. Drug availability, cultural attitudes, legal status, and preferences may affect implementation. Future analyses will evaluate the cost-effectiveness of THC:CBD.
Abstract text as indexed by PubMed for this identifier.
In practice
Why this matters
This is one of the clearer signals we have. It was an add-on to good standard care, not a replacement for it, and the benefit came with real side effects worth discussing before starting.
Browse related research
Condition: Cancer Condition: Nausea Condition: Vomiting Topic: Antiemetics Topic: CBD Topic: THC
Related on CED Clinic
Back to Daily Research and Patient Questions
Reviewed by Dr. Caplan on September 17, 2026.
This page is general education about a published study. It is not medical advice and does not create a doctor-patient relationship. For care specific to you, book a consultation.
