Background:Drug utilization evaluation(DUE)is defined by the World Health Organization(WHO)and focuses on the medical,social,and economic consequences of pharmaceutical marketing,distribution,prescribing,and usage in society.The WHO recommends a physician to every 1 000 people.According to the recent data from the Health Ministry in 2019,in which 1.16 million doctors are of active population with just 80％,or 0.9 million,practicing.As a result,a ratio of 0.68 doctors for every 1 000 people,which is much below as per the WHO reports.This article describes history,types,WHO guidelines,need and purpose of DUE.Objective:The main aim of this paper is to provide information about the rational use of medication in outpa-tient and inpatient department with special emphasis of DUEs.It also provides awareness directly to healthcare professionals,researchers,academicians,pharmacist and nurses to reduce the irrationality of medicines.Methods:The method used to compile this review information gathered from websites,Google scholar,PubMed,Research gate,and studies published on DUE from July 20 to Oct 22 were included as source of information.Results:We studied more than 35 published study on DUE,that reveals most of the physicians prescribed branded drugs not generic drugs,but WHO prescribing indicator allows to prescribe generic drugs in the hospital pharmacy to maintain better inventory control.It may also help to prevent pharmacist misunderstanding during dispensing.Conclusion:The use of generic prescription names avoids the possibility of medication product duplication and lowers patient costs.It is important to remember that incorrect medication prescriptions have impact on both patients and their family members.WHO indicators identify irrational prescribing behaviours to make therapy more rational and cost-effective.