The effect of Marinol, which contains the antiemetic tetrahydrocannabinol (THC), was evaluated in five cancer patients undergoing chemotherapy. Subjects rated their nausea and vomiting, food intake, appetite and mood status three times daily. Drug therapy (THC) or no drug was administered for an average of four months during the course of their chemotherapy regimen. Subjects began taking THC the first day of chemotherapy and continued (5mg/three times a day) for an average of two weeks. Subjects reported their nausea and vomiting to be increased while receiving THC which coincided with their period of chemotherapy treatment. Subjective ratings for food intake and appetite varied in each case and did not always correlate with actual caloric intake from food. Food intake in most subjects was approximately the same, or greater with THC even though the period when THC was given coincided with chemotherapy treatment, and the use of emetigenic drugs. This resulted in weight maintenance or minor weight loss in most subjects. The absence of THC during chemotherapy treatment resulted in decreased food intake. Some of the moods reported most frequently by subjects while receiving THC were activity, interaction, and relaxation. Depression, social withdrawal, and anxiety were reported less frequently and usually occurred around the time of chemotherapy. The majority of the moods reported indicated that subjects had positive feelings associated with THC therapy. The results of this study indicated that THC benefitted cancer patients by increasing food intake during chemotherapy regimens without causing adverse behavioral changes. / Master of Science