Background: The opioid epidemic has been declared a public health crisis, with thousands of Americans dying from overdoses each year. In 2017, Ohio passed the Opioid Prescribing Guidelines (OPG) limiting narcotic prescriptions for acute pain. The present study sought to evaluate the effects of OPG on the prescribing behavior of orthopedists following total knee arthroplasty (TKA) and total hip arthroplasty (THA). Methods: An institutional database was queried to compare morphine equivalent dose (MED) prescribed at discharge, acute follow-up (<90 >days), and chronic follow-up (>90 days) pre-OPG and post-OPG. Cases were identified over a 2-year period starting 1 year before OPG implementation. Results: Nine orthopedic surgeons performed 1160 TKAs (692 pre-OPG, 468 post-OPG) and 834 THAs (530 pre-OPG, 304 post-OPG). Total MED for TKA and THA dropped post-OPG (1602.6 ± 54.3 vs 1145.8 ± 66.1, P <.01; 1302.3 ± 47.0 vs 878.3 ± 62.2, P <.01). Much of the total MED decrease was accounted for by the decrease in discharge MED, which was the largest in magnitude (904.8 ± 16.4 vs 606.2 ± 20.0, P <.01; 948.4 ± 19.6 vs 630.6 ± 25.9, P <.01). Seven of the 9 surgeons statistically reduced mean MED prescribed at discharge following OPG. The percentage of patients receiving new narcotic scripts at acute follow-up increased post-OPG for both TKA (41.5% vs 47.2%, P =.05) and THA (18.3% vs 25.7%, P =.01). Conclusion: Orthopedists reduced total MED prescribed after TKA and THA following the onset of OPG. The majority of this decrease is explained by decreased MED at discharge. Conversely, the post-OPG period saw slightly more new narcotic scripts written during acute follow-up.