Purpose: To determine the effects of knowledge and practice variations on prescribing patterns of systemic corticosteroids (SC) for acute upper respiratory tract infections (URTI).Materials and methods: A cross-sectional evaluation of practicing otolaryngologists in the United States through the use of a 16-question Knowledge, Attitude, and Practice survey. The survey was self-administered through email delivery to practicing members of the American Academy of Otolaryngology-Head and Neck Surgery.Results: Of 349 respondents, the majority were attending physicians in private practice and used SC 25% to 50% of the time. There was a higher rate of SC use by clinicians in the Southeast United States (adjusted odds ratio [aOR], 2.10; 95% confidence intervals [95% CI], 1.18-3.72) and by those in private practice (aOR, 2.67; 95% CI, 1.63-4.37). Levels of SC knowledge did not vary across respondents; however, knowledge was associated with increased use of SC. Only 62.8% of respondents answered all 4 Knowledge questions correctly and this was associated with a 3.5-fold decrease in SC use (aOR, 0.29; 95% CI, 0.19-0.44). Attitudes toward SC use reflected prescribing practices and were also linked to levels of knowledge, as respondents with less knowledge were more likely to have a favorable outlook toward use of SC.Conclusion: Use of SC for treatment of acute URTI is associated with clinician demographics and knowledge. Otolaryngologists are more likely to use SC for acute URTI in the Southeast United States and in private practice. Knowledge and provider education are key factors in prescribing patterns.