This book is meant for the study of a serious disease - rheumatoid arthritis, which is more common nowadays in developing countries. This book sums all the contents about the disease and describes a comparative drug study of three different groups of drugs which are dexamethasone, methotrexate and leflunomide. These three drugs are commonly used nowadays for Rheumatoid Arthritis disease, but which one is best can only be determined after a comparative drug study. Thus, this book may be a milestone in the research field of Rheumatoid Arthritis.