Background: Propylthiouracil (PTU) is a thyro-suppressive medication commonly used for the treatment of hyperthyroidism, but may cause agranulocytosis, which rises the mortality of patients. Objective: To evaluate the prevalence of agranulocytosis in hyperthyroid patients after the use of Propylthiouracil. The aim of the current research is to access the drug utilization and investigation of PTU which aids in accessing rational therapy and other aspects related to the patient’s safety. Methodology: A cross- sectional study conducted from May 2016 to April 2017 at Liaquat University of Medical and Health Sciences, Hospital Hyderabad/ Jamshoro. 150 prescriptions were collected by non-probability consecutive sampling technique from the adults with Hyperthyroidism patients using Propylthiouracil. Thyroid function tests were conducted using Immunoassay Elecysis 2010. The blood profile tests were evaluated on Sysmex kx21. The collected data was evaluated using the Statistical Package for Social Sciences (SPSS). Results: The data revealed that the propylthiouracil-induced agranulocytosis in 4 hyperthyroid patients (n=2 males, n=2 females) and the prevalence of Propylthiouracil-induced agranulocytosis was 2.7%. Conclusion: It was observed that Propylthiouracil damages the hematopoietic stem cells and precursors of granulocytes in bone marrow can cause agranulocytosis.