OBJECTIVES:  To assess the costs and outcomes of parecoxib used in combination with opioids vs. opioids alone in the post-operative management of surgical patients in Greece. METHODS: A model comparing parecoxib plus opioid treatment, to opioids alone during the first three days post-surgery was developed. Clinical efficacy was based on a phase-III randomized, double-blind clinical trial that also provided the frequencies of occurrence of clinically meaningful opioid-related adverse events (CMEs) for both treatment arms. Resource use associated with each CME was elicited via strictly structured questionnaire based interviews to a panel of experts (surgeons and anesthesiologists). Cost calculations followed a third party payer perspective (Euros, 2012). Treatment effectiveness was calculated in Summed Pain Intensity scores (SPI). RESULTS: According to the clinical trial, patients under parecoxib plus opioids had lower pain scores (SPI 59.20 vs. 80.80) and fewer CMEs (0.62 vs. 1.04 per patient) compared to opioids alone, for a 3-day period. This led to a full offset of the excess cost of the addition of parecoxib and to potential savings of 858€ (total cost per patient: 819.08 vs. 1,677.08, respectively). Savings were mainly attributable to decreased CMEs, reductions in ICU and general ward bed-days as well as to reduced physician and nurse time. Results were sensitive with regards to probabilities of occurrence or co-occurrence of CMEs (>2 CMEs occurring simultaneously), although the above was of limited impact. Medication costs had a minimal impact on the results of the sensitivity analysis. Extending the model cycle to 5-days post-operatively was associated with additional savings of 1,139.9€ per patient, compared to opioid use alone (total cost per patient: 1,063.2 vs. 2,203.1 respectively). CONCLUSIONS: Parecoxib can be a valuable addition to opioid treatment for post operative pain, improving pain relief, reducing the probabilities of CME occurrence and lowering overall costs of treatment.