OBJECTIVES: Determine whether the implementation of a statewide opiate prescribing policy is associated with a decrease in the number of prescriptions for opiates for discharged emergency department patients. METHODS: Retrospective review of opiate prescriptions written by medical professionals comparing a 4 month period before and after the implementation of an opiate prescribing policy.  RESULTS: An independent samples t-test was conducted to examine the differences in the mean number of total prescriptions per patient per day, opiate prescriptions per patient per day, total number of visits per day, and total number of opiate prescriptions per day.  In the four-month period prior to implementation of the policy, there was an average of 0.196 (SD=0.005) opiate prescriptions per patient per day.  This decreased to 0.188 (SD=0.015) opiate prescriptions per patient per day in the four-month period after the policy.  The difference was not statistically significant (mean difference = 0.009; 95% CI: -0.014, 0.03; p = 0.35).  Before the policy, there was also an average of 0.84 (SD=0.015) prescriptions/day and, after the policy, this decreased to 0.79 (SD=0.04) prescriptions/day (mean difference = 0.046; 95% CI:-0.018, 0.11; p = 0.10).  The average number of total visits per day decreased over this time period (483 (SD=4.1) vs, 463 (SD=11.2); mean difference=20.2; 95% CI: 3.2, 36.8; p =0.03) as did the total number of opiate prescriptions per day (405 (SD=4.5) vs 367 (SD=27.9); mean difference=37.7; 95%CI: -4.9, 82.7; p = 0.07).  CONCLUSIONS: Controlling for daily emergency department volume and total prescriptions, the proportion of prescriptions written for opiates remained relatively unchanged with the implementation of a statewide opiate prescribing policy. This may indicate that the effect of prescribing policies cannot be accurately measured using number of prescriptions written. Alternatively, quantity of pills per prescription may be a more appropriate measure of such a policy’s success.