Cost-effectiveness model was adopted to the Hungarian health care settings in order to evaluate the costs, effectiveness and cost-effectiveness of two years comparison of zoledronic acid therapy (5mg infusion over 15 minutes given once) with risedronate therapy (30mg/day orally given for 2 months), alendronate therapy (40mg/day orally given for 6 months), tiludronate therapy (400mg/day orally given for 3 months) and pamidronate therapy (180mg I.V. in 6 weeks) in patients with Paget's disease of bone. The long term outcome was evaluated by the cost per time in response over two years period. The measure of effect the time patients are in response was based on SAP measurement. Data sources were randomized clinical trials of treatments in PDB, literature and expert opinion. The analysis was performed from a society perspective. Discounting rate of 6% was applied for costs and effects in the second year. A standard costing methodology was used, according to the patterns of care currently in use in Hungary. Costs were calculated to cover medical procedures performed in two years time frame for patients with PDB and include direct costs of treatment and follow-up (visit to physicians offices, prescription of medication, laboratory procedures and treatment costs of side effects. As a result zoledronic acid dominated all the other therapies compared, hence it was the most effective and the least expensive in the treatment of Paget's disease of bone.