Cannabis in Cancer Care: Strongest Evidence for Nausea and Vomiting | Research

The takeaway

A scoping review of 35 studies found cannabinoids show promise for managing cancer-related nausea/vomiting (studied in 77% of trials), appetite loss, and pain, with THC being the most commonly studied cannabinoid.

Oncologists, cancer patients, and medical cannabis researchers

77% of studies focused on nausea/vomiting; only 9% on pain

What the researchers found

Of 35 studies (29 randomized, 6 non-randomized), 77.1% evaluated cannabinoids for nausea and vomiting, 11.4% for appetite, 8.6% for pain, and 2.9% for tumor regression. THC was the most studied natural cannabinoid. About 57% used registered pharmaceutical products. Only one study detailed cancer staging, highlighting a gap in the literature.

Why it matters

Despite widespread use of cannabis by cancer patients, the evidence base is heavily skewed toward nausea/vomiting. Pain and appetite, which are among the most common reasons patients use cannabis, have far less rigorous evidence supporting their use.

The numbers in context

35 studies (29 RCTs, 6 non-randomized). Nausea/vomiting: 77.1%. Appetite: 11.4%. Pain: 8.6%. Tumor regression: 2.9%. THC most studied. 57.1% used registered products. 62.9% specified cancer types (breast, lung, sarcomas, hematological, reproductive).

How the study worked

Scoping review following JBI guidelines. Searched Cochrane, Embase, CINAHL, PubMed, LILACS, Google Scholar, and gray literature. Included primary studies (observational and randomized) evaluating cannabinoid efficacy and safety in cancer patients.

What this study cannot tell us

Scoping review maps the literature but does not assess quality or pool results. Study heterogeneity in doses, formulations, and cancer types limits comparisons. Only one study addressed cancer staging, making dose-response analysis across disease severity impossible.

How to read the evidence

Comprehensive scoping review following JBI guidelines, though it maps evidence without assessing quality.

When this study was published

2024 scoping review

The bigger picture

The concentration of evidence around nausea/vomiting reflects historical research priorities (cannabinoids were first approved for chemotherapy-induced nausea). As cancer care evolves and patients increasingly self-medicate with cannabis, research needs to expand to match actual use patterns.

Questions still open

Why is there so little research on cannabinoids for cancer pain specifically? Would tumor-type-specific studies show different results? How does cancer staging affect cannabinoid efficacy?

Common questions

What is cannabis most studied for in cancer?

Nausea and vomiting, which was the focus of 77% of the 35 studies in this review. Appetite, pain, and tumor effects had far fewer studies.

Does cannabis help with cancer pain?

The evidence is limited. Only 8.6% of studies in this review addressed cancer pain, despite it being one of the most common reasons cancer patients use cannabis. More research is needed.

Read the original research

Medical cannabis use in oncology and associated outcomes: A scoping review.

Journal of oncology pharmacy practice : official publication of the International Society of Oncology Pharmacy Practitioners, 30(4), 737-751

View on PubMed ↗Publisher’s paper ↗

Citation

Valente, Ana Carolina; Lopes, Luis Phillipe Nagem; Matheus, Maria Eline. (2024). Medical cannabis use in oncology and associated outcomes: A scoping review.. Journal of oncology pharmacy practice : official publication of the International Society of Oncology Pharmacy Practitioners, 30(4), 737-751. https://doi.org/10.1177/10781552241239006