Antiemetics are ordered to control nausea and vomiting in the child undergoing chemotherapy. How can the nurse most effectively use these medications?

Choice A rationale Antiemetics are most effectively used by administering them proactively, before the chemotherapy agent is started, which is known as prophylactic use. This method allows the medication to achieve therapeutic serum levels and occupy receptors before the emetogenic chemicals stimulate the vomiting center in the brain, thus blocking the nausea pathway. Choice B rationale Waiting for nonpharmacologic methods to fail before using antiemetics is ineffective management. Chemotherapy-induced nausea and vomiting are best controlled with aggressive, scheduled pharmacologic intervention from the start, as it is far harder to stop vomiting once the emetic cycle has been established. Choice C rationale Starting antiemetics only when nausea begins is reactive and allows the patient to experience unnecessary distress and potential nutritional compromise. The goal in chemotherapy management is prevention; therefore, antiemetics must be started before the patient's exposure to the emetogenic stimuli. Choice D rationale Providing antiemetics as needed, or PRN, is a less effective strategy for chemotherapy-induced nausea and vomiting. The intensity of this type of emesis necessitates a scheduled regimen to consistently maintain therapeutic drug levels and prevent the overwhelming onset of nausea and vomiting, which can be difficult to manage once it starts.