Background: The American Society of Clinical Oncology (ASCO) launched the Quality Oncology Practice Initiative (QOPI) program in 2010, to promote quality cancer care. Subsequently, ASCO has influenced the use of the neurokinin 1 (NK1) receptor antagonists aprepitant/fosaprepitant through peer-reviewed publications and the Choosing Wisely Campaign. These agents increase cost and, via CYP3A4 inhibition, may lead to drug interactions. Here we report our survey results that explored prescribing patterns of these agents among QOPI-certified and non-certified oncologists. Methods: An anonymous online survey was distributed to oncologists in four states. Respondents were asked 12 questions about the use of aprepitant/fosaprepitant in their clinical practice. Responses were analyzed in aggregate using likelihood ratio Chi-square tests. P-values of < 0.05 are significant. Descriptive statistics describe differences between groups. Results: We analyzed 157 responses and excluded 10 respondents that did not identify themselves as medical oncologists. 62.1% of the practitioners practice in a QOPI-certified practice (90/145). Compared with non-QOPI practitioners, QOPI physicians are significantly more likely to use NK1 antagonists with intermediate/low emetogenicity regimens like weekly cisplatin for head & neck cancer (83.3 vs. 28.0%, p: < 0.001), cervical & bladder cancer (85.2 vs. 34.0%, p: < 0.001), and with CHOP ± rituximab for lymphoma (82.4 vs. 18.0%, p: < 0.001). Significantly, the majority of QOPI-certified physicians report using these agents for the sole purpose of earning/maintaining QOPI certification (81.4-85.4%). QOPI-certified physicians are also significantly more likely to appropriately prescribe NK1 antagonists with doxorubicin ≥ 60 mg/m² (86.4 vs. 51.9%, p: < 0.001), cisplatin ≥ 50 mg/m² (96.3 vs. 76.9%, p: < 0.001) and dacarbazine (84.6 vs. 55.8%, p: < 0.001). Conclusions: Although QOPI-certified physicians are significantly more likely to use NK1 antagonists than non-QOPI physicians, our findings indicate that their motivation is to satisfy QOPI guidelines instead of perceived necessity. A prospective study may be beneficial to further define the role of NK1 antagonists with intermediate/low emetogenicity regimens.