Efficacy and Safety of Low-Dose Olanzapine for the Prevention of Chemotherapy-Induced Nausea and Vomiting in Patients Receiving Platinum-Based and AC-T Regimens: A Prospective Observational Study

Background: Chemotherapy-induced nausea and vomiting (CINV) is a prevalent and distressing side effect experienced by cancer patients undergoing platinum-based and AC-T chemotherapy regimens. Despite advancements in antiemetic strategies, a substantial proportion of patients continue to experience inadequate control of CINV, leading to compromised quality of life and treatment compliance. Objective: To evaluate the efficacy and safe ty of low-dose olanzapine, when administered alongside standard antiemetic therapy, in preventing both acute and delayed phases of CINV. Methods: A prospective, randomized, controlled observational cohort study was conducted at the Department of Oncology, Government General Hospital, Guntur, India, from February 2024 to April 2024. Eighty eligible patients were randomized into two groups: standard antiemetics alone (n=40) and standard antiemetics with low-dose olanzapine (5 mg daily) (n=40). Incidence and severity of CINV were assessed during acute (0–24 h) and delayed (24–120 h) phases. Results: The addition of low-dose olanzapine significantly reduced both incidence and severity of acute and delayed CINV compared to control (p<0.05). A higher proportion of patients in the olanzapine group achieved complete response (no emesis, no rescue medication). Adverse events were mild and comparable between groups. Conclusion: Low-dose olanzapine is an effective and well-tolerated adjunct for CINV prevention in platinum-based and AC-T regimens. These results support its inclusion in standard antiemetic protocols.