Cannabis in Cancer Care: Strongest Evidence for Nausea and Vomiting

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.

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.

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 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.

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.