Electronic Physician (ISSN: 2008-5842) http://www.ephysician.ir April 2017, Volume: 9, Issue: 4, Pages: 4251-4254, DOI: http://dx.doi.org/10.19082/4251 Corresponding author: Bahman Ahadinezhad, Department of Health Management and Economics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran. Email: bahmanahadi2009@gmail.com Received: February 29, 2016, Accepted: August 15, 2016, Published: April 2017 iThenticate screening: July 28, 2016, English editing: December 10, 2016, Quality control: February 12, 2017 © 2017 The Authors. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial- NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made. Page 4251 The structure of the pharmaceutical market in Iran using concentration indices Mohammad Mohseni 1 , Hasan Abolghasem Gorji 2 , Bahman Ahadinezhad 3 , Omid Khosravizadeh 4 , Meysam Safi Keykaleh 5 , Ahmad Moosavi 6 , Bahareh Mohtashamzadeh 2 1 Health Management and Economics Research Center, Iran University of Medical Sciences, Tehran, Iran 2 School of Health Management and Information Sciences, Iran University of Medical Sciences, Tehran, Iran 3 Department of Health Management and Economics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran 4 Social Determinants of Health Research Center, Qazvin University of Medical Sciences, Qazvin, Iran 5 School of Health, Safety and Environment, Shahid Beheshti University of Medical Sciences, Tehran, Iran 6 Department of Health and Community Medicine, Dezful University of Medical Sciences, Dezful, Iran Type of article: Original Abstract Background and objective: The efficiency and function of the pharmaceutical sector, as a vital portion of the health system, have a significant effect on intermediate and final indices of health. In this research, the structure of the pharmaceutical market in Iran was examined through the calculation of concentration indices in 2011. Methods: In this cross-sectional study, the needed data was gathered from the Food and Drug Administration in the year 2011. Data were analyzed using SPSS software version 20 and Microsoft Office Excel software. Finally, two common measures of market concentration, the Concentration Ratio and the Herfindahl-Hirschman Index, were calculated. Results: The largest and the smallest shares of the industry were 5.57% and 0.01%, respectively. The average industry share was 1.09%. The share range was calculated to be 5.56%. The Herfindahl-Hirschman Index was 248.5, which indicates a very low concentration of the pharmaceutical market in Iran. Also, based on the Concentration Ratio of 4 companies (18.39%), the concentration of the pharmaceutical market has been too low. Conclusion: The pharmaceutical market in Iran has a very low concentration and it does not have an exclusive mode in terms of market structure. Therefore, it can be attributed to the competitive model. The policy makers in this area can use this characteristic as a leverage to improve efficiency, fairness, revenue and health indices. Keywords: Drug, Pharmaceutical Market, Concentration, Index, Iran 1. Introduction Nowadays, the pharmaceutical industry is gradually gaining the number one position among the different industries throughout the world (1). Products of the modern pharmaceutical industry have improved the outlook for patients with many different disorders. Pharmaceutical companies have been successful in drug manufacturing based on scientific explorations. Despite these successes, pharmaceutical companies have been increasingly publicly criticized (2, 3). Despite lower prices of drugs in international markets, accessing some of the essential medicines is difficult (4). Many patients in poor countries cannot get access to the drugs required for their treatments because of the high prices of the medicines. The prices are set by producers who benefit from an exclusive opportunity (5). The competition is therefore influenced by market concentration and this issue is a key concern of agencies, policy makers and legislators (6). Furthermore, the investigation of impacts of policies focusing on improving equity and equality in access to required medicines, is a matter of great importance to efficiency in the pharmaceutical industry (1). The pharmaceutical market size in Iran has increased 6.8 % in terms of volume and 18.5 % in terms of value since 2001 (7). The growth rate of this market has been considerable in Asia. The reasons for increased dependence