OBJECTIVES: Standard medicinal care of patients with urge or mixed urinary incontinence is muscarinic receptor antagonists. Alternative forms of administration are available for these drugs. The objective of this analysis was to compare the cost effectiveness of the only available transdermal oxybutynin patch with oral long-acting tolterodine tablets in the treatment of patients with urge or mixed urinary incontinence in Sweden. METHODS: The efficacy of oxybutynin patches (3.9 mg/day), and tolterodine tablets (4 mg/day) was compared in a 12 weeks randomized clinical trial with 361 patients. The study demonstrated a comparable clinical efficacy between the treatment alternatives in number of daily incontinence episodes, average void volume and QoL. A cost minimization analysis (CMA) was performed based on this trial where direct medical costs related to drug treatments and the costs of treating the major adverse events (AE) (erythema, pruritus, rash, dry mouth, diarrhoea and constipation) were included. Resource utilization associated with the treatment of the adverse events in Swedish clinical practice was assessed by Swedish specialists in the field. RESULTS: The CMA shows that the total costs for 12 weeks tolterodine treatment is 1113.- SEK (~119.- €) per patient while the total costs for 12 weeks oxybutynin treatment is 1067.- SEK (~114.- €). The results also demonstrate that the cost of treating AEs compose an insignificant fraction of the total treatment costs. This is due to the low frequency of AEs requiring treatment, together with the low costs for treating each AE. A number of sensitivity analyses demonstrate the robustness of the results, including various scenarios for extrapolating the findings over 52 weeks. CONCLUSION: This CMA finds that oxybutynin patches (3.9 mg/day) is a cost-effective treatment alternative to tolterodine tablets (4 mg/day) for treating patients with urged or mixed urinary incontinence in Sweden.