This thesis explores the research-based different pathomechanisms of agranulocytosis caused by methimazole. The thesis is also supported by the case study of methimazole induced agranulocytosis, which the author conducted at the Wyckoff Heights Medical Center in Brooklyn, New York. The rate of relapse, remission related to different doses of methimazole, and whether methimazole will be used before or after radioactive isotope therapy are also explored. Recent studies on the use of Diclofenac and Rituximab to decrease and prevent the opthalmopathy associated with Grave's disease are also analyzed.