An economic evaluation has been performed, analysing direct medical costs for the treatment of perennial allergic rhinitis (PAR) with budesonide aqueous nasal spray and fluticasone propionate nasal spray in Canada. BACKGROUND: 314 patients, with at least a one-year history of PAR, were randomised into a double-blind, parallel group study of 6 weeks duration. The treatments were budesonide 256 ?g, fluticasone propionate 200 ?g, or placebo. Budesonide was significantly more effective than fluticasone in reducing “blocked nose”. Both active treatments produced significantly lower mean scores for overall nasal symptoms compared with placebo, and both were well tolerated. METHOD: A cost-minimasation analysis, utilizing the clinical trial data, was performed of the total costs of 1) budesonide-based and 2) fluticasone-based treatment strategies, including the relative importance of the drug cost in both strategies. RESULTS: In Canada, the average treatment cost per patient over 12 months in the budesonide group was CAN$ 389.85 which was 23.3 % lower than in the fluticasone group, CAN$ 508.06, due to lower drug acquisition costs. Drug costs represented between 24.6% and 42.1 % of total treatment costs for the budesonide and the fluticasone group, respectively. CONCLUSION: Budesonide aqueous nasal spray is a cost-effective strategy in the treatment of perennial allergic rhinitis. “ECONOMIC & OUTCOMES ISSUES OF INFECTIOUS DISEASE”