OBJECTIVES: . Inappropriate analgesia in postoperative pain (POP) raises hospitalization costs and increases the burden of several surgeries with a meaningful impact over patient’s quality of life. The objective of this study was to develop an economic analysis to evaluate parecoxib, ketorolac and morphine in the treatment of POP in patients who underwent total hip arthroplasty from an institutional perspective METHODS: A cost-effectiveness analysis was developed using a Bayesian decision-tree model, to simulate costs and effectiveness outcomes over the postoperative hospitalization period (15 days). Comparators were multimodal analgesics: morphine (52 mg/day) plus parecoxib (40 mg/day); morphine (52 mg/day) plus ketorolac (90 mg/day) and morphine (57 mg/day) alone. Effectiveness measures were: percentage of treatment response without adverse events (AE) meeting the highest score of the patient’s global evaluation survey (excellent). Effectiveness data and transition probabilities were collected from international published literature. Resource use and cost data was gathered from hospital records of patients undergoing total hip arthroplasty at the Social Security Mexican Institute (IMSS) (n=89). The model was calibrated according to international pharmacoeconomics guidelines. One-way and probabilistic sensitivity analyses were performed with Monte Carlo Simulation second-order approach  RESULTS: Patients who received parecoxib exhibited 41% of treatment response, followed by morphine (26%) and ketorolac (24%). Estimated costs per patient were lower with parecoxib (US$ 5,439.30) followed by ketorolac (US$5,538.91) and morphine (US$5,553.71). No statistical differences were found among the costs of analgesic therapies (p>0.05). Parecoxib showed a weak dominance against its competitors. Acceptability curves showed parecoxib as the most cost-effective therapy with 95% when willingness to pay is US$6,500.  CONCLUSIONS: Results show that at the IMSS, parecoxib is a cost-effective treatment that significantly reduces POP in patients who underwent total hip arthropasty. This information could be useful for developing markets healthcare institutions in order to establish efficient analgesics improving current health outcomes