Treatment of side effects associated with antineoplastic therapy is the indication for cannabinoids which has been most documented, with about 40 studies (THC, nabilone, other THC analogues, cannabis). Most trials were conducted in the 1980s. THC has to be dosed relatively highly, so that resultant side effects may occur comparatively frequently. THC was inferior to high-dose metoclopramide in one study. There are no comparisons of THC to the modern serotonin antagonists. Some recent investigations have shown that THC in low doses improves the efficacy of other antiemetic drugs if given together. In folk medicine cannabinoids are popular and are often used in other causes of nausea including AIDS and hepatitis.
resource: International Association for Cannabinoid Medicine