Harrison's Principles of Internal Medicine 21st edition by Joseph Loscalzo (Author), Anthony Fauci (Author), Dennis Kasper (Author), Stephen Hauser (Author), Dan Longo (Author), J. Larry Jameson  (Author) Harrison’s is world-renowned as the most authoritative source for:  • Clear, concise schemas that facilitate the generation of differential diagnoses to reason efficiently through complex real world clinical cases • The physiologic and etiologic basis of signs and symptoms, which are covered through a wealth of unsurpassed expert guidance and linked to the disease-specific chapters that follow • Updated clinical trial results and recommended guidelines • Excellent and extensive visual support, including radiographs, clinical photos, schematics, and high-quality drawings • Coverage of both therapeutic approaches and specific treatment regimens • Practical clinical decision trees and algorithms • Organ/system-specific sections, with clinically relevant pathophysiology and practical clinical advice on the approach to the patient, strategies towards building a differential diagnosis, outstanding clinical algorithms and diagnostic schema, a wealth of clinical images and diagrams, current clinical guidelines, and general and specific approaches to therapy Harrison’s remains the most trusted resource in a world influenced by endless sources of medical information. The most timely and comprehensive updates from the world’s top experts are featured in the 21st edition:  • Current coverage of the diagnosis and treatment of diseases, from COVID to dementia to sepsis to multiple sclerosis to lung cancer • Updated content that reflects new approved therapeutics and new practice-changing guidelines and evidence summaries • More than 1000 clinical, pathological, and radiographic photographs, diagnostic and therapeutic decision trees, and clear schematics and diagrams describing pathophysiologic processes • Numerous atlases featuring curated collections of important visual aspects of diagnosis and management • Updated and time-saving curation and synthesis of established and new medical literature and studies • Clinically relevant coverage of disease mechanics and pathophysiology, and related therapeutic mechanisms