Background and Objectives: Awareness about prescribing pattern and comparing that with standards of the World Health Organization (WHO) can affect health policy-makers in adopting policies and implementing necessary interventions for rational use of drugs. The aim of this study was to determine the pattern of drug prescribing in outpatients covered by Social Security Organization in Semnan province.

Material and Methods: In this study, 952,712 prescriptions in Semnan province in 1396 were investigated and indicators of use of drugs include average price of each prescription, average number of drugs in each prescription, percentage of prescriptions containing 4 drugs or more, percentage of prescriptions containing antibiotics, injections and corticosteroids, physicians by specialty and by the length of activity were extracted and compared with those provided by the WHO standards.

Results: The average price of prescriptions was 254,377 IRR and average number of drugs per prescription was 2.65. Generally, 26.9 percent of the prescriptions included 4 or more drugs. Percentage of the prescriptions containing antibiotics, injections and corticosteroids was 55 percent, 29 percent and 11.1 percent, respectively. All of the examined indicators were higher than the recommended level by the WHO.

Conclusion: This study showed some evidence of irrational drug prescription especially in the polypharmacy, antibiotics and injectable drugs. Therefore, it is suggested that adequate supervision of the prescribing and training of prescribing principles for physicians should be considered in continuing education programs.