PURPOSE/OBJECTIVES To obtain information about the knowledge and attitudes of oncology nurse practitioners (ONPs) concerning the effect of direct-to-consumer (DTC) advertising of prescription medications on prescribing patterns. DESIGN Exploratory survey. SETTING Oncology Nursing Society Nurse Practitioner Special Interest Group members in the United States. SAMPLE 221 of 376 ONPs completed the survey (58%). METHODS Researcher-developed 12-question postal survey. MAIN RESEARCH VARIABLES Knowledge and attitudes of ONPs on DTC advertising effects on prescribing patterns. FINDINGS The findings were similar to those of previous studies of physicians regarding the number of visits when patients requested DTC-advertised medications. Major differences were the positive attitudes of ONPs toward potentially longer patient visits to explain and educate patients regarding medication requests based on DTC advertising and smaller percentages of ONPs who felt "pressured" to prescribe requested medications. CONCLUSIONS ONPs have mixed opinions regarding the practice of DTC advertising but do not believe that they are influenced heavily by advertising with regard to prescriptive practices. ONPs consider patient encounters for education purposes as appropriate and include information about requested DTC-advertised medications in their approach to patient care. IMPLICATIONS FOR NURSING This is an exploratory survey of a specialty group of ONPs. More research is needed to further explore the practice of DTC advertising and potential influences on the prescribing patterns of ONPs. DTC advertising of prescription medications is increasing; ONPs need to increase their knowledge base about the potential for influences of prescriptive practices.