Zofran (ondansetron) is used to prevent nausea and vomiting caused by surgery or cancer medicines. Includes Zofran side effects, interactions and indications. Ondansetron is used to prevent nausea and vomiting caused by surgery, chemotherapy, or radiation by blocking nausea-triggering chemicals in the body. Detailed dosage guidelines and administration information for Zofran (ondansetron hydrochloride). Includes dose adjustments, warnings and precautions. Detailed Ondansetron dosage information for adults and children. Includes dosages for Nausea/Vomiting, Nausea/Vomiting - Chemotherapy Induced, Nausea/Vomiting - Postoperative and more; plus renal, liver and dialysis adjustments. Easy-to-read patient tips for Zofran covering how it works, benefits, risks, and best practices. Learn about the side effects of ondansetron, from common to rare, for consumers and healthcare professionals. Learn about the side effects of Zofran (ondansetron), from common to rare, for consumers and healthcare professionals. Zofran Injection package insert / prescribing information for healthcare professionals. Includes: indications, dosage, adverse reactions and pharmacology. A major drug interaction exists between Methadone and Zofran. View detailed information regarding this drug interaction. Ondansetron Interactions There are 374 drugs known to interact with ondansetron, along with 2 disease interactions. Of the total drug interactions, 134 are major, 233 are moderate, and 7 are minor.