1. What is an ExpertConsult Activation Code? An ExpertConsult activation code is a unique alphanumeric string (typically 10–20 characters) that grants online access to a specific medical or veterinary textbook’s digital content. It is included with the purchase of new print copies of many Elsevier textbooks (e.g., Gray’s Anatomy , Nelson Textbook of Pediatrics , Robbins & Cotran Pathologic Basis of Disease ).