A nurse is caring for a client who is receiving ondansetron IV. Which of the following findings is an indication that the ondansetron is effective?

The correct answer is D: Decreased nausea. Ondansetron is an antiemetic medication used to treat nausea and vomiting. Therefore, a decrease in nausea indicates that the medication is effective in managing the client's symptoms. Increased urinary output (A) is not a direct effect of ondansetron and is not a reliable indicator of its effectiveness. Reduced dizziness (B) and absence of peripheral neuropathy (C) are not specific to the action of ondansetron and do not directly relate to its effectiveness in treating nausea.