Internal Medicine is the backbone of clinical practice and the most extensive subject in postgraduate and international medical examinations. This book, “Internal Medicine – A Complete MD & USMLE Review,” is a comprehensive, system-based, exam-oriented textbook designed to meet the needs of MD Medicine residents, USMLE aspirants, PLAB candidates, NEXT examinees, and practicing physicians worldwide. The book is structured into 20 meticulously organized units, covering every major system in Internal Medicine, including Cardiology, Respiratory Medicine, Gastroenterology, Hepatology, Nephrology, Endocrinology, Hematology, Neurology, Rheumatology, Infectious Diseases, Oncology, Geriatrics, Emergency & Critical Care, Nutrition, Dermatology, Psychiatry, Immunology, Preventive Medicine, and Medical Ethics.