Are cannabinoids effective for the management of chemotherapy induced nausea and vomiting?

Nausea and vomiting are common side effects in cancer patients treated with chemotherapy. Proper control of these symptoms might improve quality of life in these patients. Addition of cannabinoids to standard antiemetic treatment has been proposed in order to improve control of these symptoms.

To answer this question we used Epistemonikos, the largest database of systematic reviews in health, which is maintained by screening multiple information sources, including MEDLINE, EMBASE, Cochrane, among others. We extracted data from the systematic reviews, reanalyzed data of primary studies, conducted a meta-analysis and generated a summary of findings table using the GRADE approach.

We identified 16 systematic reviews that include 61 primary studies. Out of these, four were randomized trials that answered our question. At present, given that the certainty of the evidence is very low, it is unclear whether the addition of cannabinoids to standard antiemetic regimes benefits patients with chemotherapy induced nausea and vomiting. Cannabinoids probably increase adverse effects substantively.