BackgroundAccording to World Health Organization (WHO) estimation, more than half of all pharmaceutical products are inappropriately prescribed, distributed, and sold and more than half of all patients use the medicines prescribed for them incorrectly. As more than 40% of therapeutic costs are pharmaceutical costs, this implies a significant waste of health resources in the world.ObjectivesTo find effective factors in irrational prescription of corticosteroids in Iran and design suitable interventions to decrease prescription rates of corticosteroids.Materials and MethodsA qualitative study was performed in 2009 on fifteen general practitioners in two groups identified by high and low corticosteroid prescription rates. Data analysis was performed by thematic analysis and the study's validity was based on training interviewers, use of interview guide, avoidance of imposing opinions, coding by two independent persons and use of all opinions obtained in the analysis.ResultsThe effective factors in irrational prescription of corticosteroids can be divided into four categories: lack of knowledge, patient-physician relationship in terms of monetary cost, poor availability of proper alternative medicines and weak supervision of regulatory bodies. As the same results were found in both groups regarding the role of regulatory organizations and availability of alternative medicines, it seems that interventions in knowledge and the patient-physician relationship which were different in the two groups can be more effective for reduction of prescription in high rate prescribers although intervention in regulatory supervision and medicine availability could have a moderate effect in both groups. In addition the common feature in all the above categories was the gap between knowledge and actual practice which is significant on three regulatory levels, supervisors, physicians and patients, and should be noted for intervention design.ConclusionsThe interventions applied in other countries can also be effective in decreasing irrational prescription of corticosteroids in Iran. These interventions include: standard clinical guidelines, essential medicines list, practical workshops, purposeful training based on problem-solving, training of all parties including pharmacists and patients, improved regulatory mechanisms, availability of assured quality medicines, availability of suitable alternatives to painkillers and realistic rational prescription policy.