OBJECTIVES: To compare the impact of different pharmacotherapies on the cost of exacerbation of COPD in public hospitals in Hong Kong METHODS: This was a retrospective study comparing the cost of management of chronic obstructive pulmonary disease (COPD) in patients from a public hospital perspective in Hong Kong. Institutional ethics approval was obtained.  The patients were above 65 years with a diagnosis of COPD of stage 3 or above based on the GOLD guideline. COPD was defined based on ICD-9-CM codes. Two cohorts of patients were included: 1) Those who received fluticasone propionate and salmeterol, plus ipratropium bromide and salbutamol inhalation, and 2) Those who received ipratropium bromide and salbutamol, and beclomethasone inhalation.  Patients were followed for 6 months before and after medications. The date one of the therapies started was the index date. RESULTS: A total of 75 patients were recruited over January to June 2008. All values are expressed as mean±SD. The number of emergency room visits and cost of visits before and after the index date for both cohorts did not show a significant difference (1.86±2.5 days vs. 1.62±1.93 days and HKD1061±1442 vs. HKD924±1102 for cohort 1, 1.15±1.28 days vs. 1.02±1.29 days and HKD657±730 vs. HKD582±735 for cohort 2, p>0.1). There was a trend of reduction in hospitalization days and cost of stay before and after the index date for cohort 1 (although not reaching a significant level) but not in cohort 2 (20.6±28.4 days vs. 15.6±18.8 days and HKD68162±93875 vs. HKD51662±66278 for cohort 1, 11.1±13.5 days vs. 10.2±13.2 days and HKD36730±44604 vs. HKD33860±43571 for cohort 2, p>0.1). CONCLUSIONS: A trend of reduction in hospital stay was demonstrated (although not statistically significant) in patients after receiving combination therapy of fluticasone propionate and salmeterol plus ipratropium bromide and salbutamol. This is consistent with earlier studies in other countries. A larger number of patients is required to prove the significance of this finding.