Drug and Disease Classification Overview

Drug and Disease Classification

• ATC (Anatomical Therapeutic Chemical) Classification: Organ/system and therapeutic, pharmacological, and chemical properties define drug groups.
• ATC/DDD Methodology: Uses ATC for classification and DDD (Defined Daily Dose) as a measurement unit; average daily maintenance dose in adults for primary indications.
• DDD Importance: Facilitates comparing drug consumption data internationally despite varying nomenclature, packaging, pricing, and dosages.
• ATC Classification Principles: Drugs are classified by primary therapeutic use, having single ATC codes per route of administration (ROA), multiple codes for distinct therapeutic uses with different ROAs or strengths.
• International Classification of Diseases (ICD): Provides a global language for disease reporting and monitoring, enabling consistent data comparison across hospitals, regions, and time periods.
• ICD History: Evolved from initial models, with ongoing revisions every decade. Florence Nightingale pioneered early data collection, Jacques Bertillon developed cause-of-death classifications, and the American Public Health Association recommended periodic revisions.
• ICD Use: Used by physicians, nurses, researchers, health information professionals, policymakers, insurance companies, and patient groups. Translated into 43 languages, primarily for mortality data reporting.

Drug Dictionaries and Coding in Pharmacovigilance

• International Nonproprietary Names (INN): Globally recognized, unique names for pharmaceutical substances (active pharmaceutical ingredients) for clear identification, safe prescription, and communication among health professionals. Introduced in the 1950s.
• MedDRA (Medical Dictionary for Regulatory Activities): Clinically validated international medical terminology developed by ICH (International Council for Harmonization) for regulatory authorities. Used for drug safety data entry, retrieval, evaluation, and presentations during pre- and post-authorization phases. Maintained by MedDRA's Maintenance and Support Services Organization (MSSO), with bi-annual updates.
• WHO Drug Dictionary: International classification of medicines created by WHO for drug monitoring, detailed information on all medical products, providing standardized information and data groupings. Regularly updated.
• EudraVigilance Medicinal Product Dictionary (EVMPD): Standard method for collecting, reporting, coding, and evaluating data on authorized and investigational medical products in the EU, considering data source uncertainties; supports data analysis. Provides multiple dictionaries within the EudraVigilance system for diverse applications.

Information Resources in Pharmacovigilance

• Pharmacovigilance: Science of detecting, evaluating, understanding, and preventing adverse effects or drug-related problems.
• Drug Information Resources: Current, critically evaluated, relevant data on drugs and their uses in specific patient situations; using primary, secondary, and tertiary resources to gather appropriate information. Using the most recent and critically examined information is important for relevance.
• Basic Drug Information Resources: Current data examining drug use; data must be relevant to the patient parameters, objectives, and alternative approaches.
• Specialized Resources for Adverse Drug Reactions (ADRs): Focus on specific ADRs within broader drug information.

Establishing Pharmacovigilance Programmes

• Hospital Programs: Focused on establishing procedures, structures, and protocols for monitoring and reporting ADRs.
• Industry Drug Safety Departments: Establishing structure and function for adverse event surveillance.
• Contract Research Organizations (CROs): Offering support and services for the establishment and operation of programs, including data analysis.
• National Programs: Ensuring that national-level programs are established to support the overall public health strategy.