Medical Dictionary for Regulatory Activities (MedDRA)
MedDRA is an international medical terminology used to code, classify and group medicine adverse event reports in the Database of Adverse Event Notifications, supporting consistent safety monitoring and regulatory reporting.
The Medical Dictionary for Regulatory Activities (MedDRA) is an internationally used set of terms relating to medical conditions, medicines and medical devices. We use it to code adverse event reports.
It was created to assist regulators with sharing information, but is also used by related industries, academics, health professionals and other organisations that communicate medical information.
MedDRA terms in the Database of Adverse Event Notifications - medicines
We use MedDRA terms for coding the reports we receive about adverse events.
Before a report is entered into the Database of Adverse Event Notifications - medicines, the relevant MedDRA terms are assigned to describe the adverse event and other medical terms.
Using this consistent terminology allows related adverse events to be grouped together in the medicine summary section of the DAEN - medicines.
MedDRA terms
the MedDRA includes standardised terms for:
- symptoms, signs, diseases, syndromes and diagnoses
- medical device malfunctions
- medication errors
- medical, social and family history information
- sites, such as application, implant and injection sites
- medical and surgical procedures
- approved uses for medications and medical devices
- types of investigations such as liver function analyses and metabolism tests.
MedDRA system organ classes
The MedDRA system organ class is the highest level of the MedDRA terminology, classified by anatomical or physiological system, aetiology (disease origin) or purpose. Most classes describe disorders of a specific part of the body. For example:
- Cardiac disorders describe heart problems
- Renal and urinary disorders describe kidney and bladder problems
- Some of the system organ classes are not related to a particular part of the body. For example:
- Investigations describes laboratory tests and other medical investigations that gave an unusual reading
- Neoplasms describes any type of growth, including cancer, no matter where it appears in the body.
The 27 MedDRA system organ classes
- Blood and lymphatic system disorders
- Cardiac disorders
- Congenital, familial and genetic disorders
- Ear and labyrinth disorders
- Endocrine disorders
- Eye disorders
- Gastrointestinal disorders
- General disorders and administration site conditions
- Hepatobiliary disorders
- Immune system disorders
- Infections and infestations
- Injury, poisoning and procedural complications
- Investigations
- Metabolism and nutrition disorders
- Musculoskeletal and connective tissue disorders
- Neoplasms benign, malignant and unspecified (including cysts and polyps)
- Nervous system disorders
- Pregnancy, puerperium and perinatal conditions
- Psychiatric disorders
- Renal and urinary disorders
- Reproductive system and breast disorders
- Respiratory, thoracic and mediastinal disorders
- Skin and subcutaneous tissue disorders
- Social circumstances
- Surgical and medical procedures
- Vascular disorders
- Product issues.
MedDRA reaction terms
The term used to describe an adverse event in the Database of Adverse Event Notifications - medicines is the MedDRA 'preferred term', which describes a single medical concept.
Each MedDRA system organ class has a number of MedDRA preferred terms associated with it. For example, the system organ class 'cardiac disorders' includes (among others) the following preferred terms:
- angina
- cardiac arrest
- myocardial infarction
- palpitations.
The MedDRA Maintenance and Support Services Organization
The MedDRA Maintenance and Support Services Organization (MSSO) maintains and distributes MedDRA information. The MSSO releases updated versions of MedDRA twice a year to subscribers.
MedDRA was developed by the International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH) to assist regulatory authorities to easily and accurately share information on therapeutic goods, including about adverse events to medicines.
MedDRA terminology incorporates terminology from the:
- Medicines and Healthcare products Regulatory Agency (MHRA)
- World Health Organization Adverse Reaction Terminology (WHO-ART)
- International Classification of Diseases (ICD)
- International Classification of Diseases and Clinical Modification (ICD-CM)
- Coding Symbols for a Thesaurus of Adverse Reaction Terms (COSTART)
- Japanese Adverse Reaction Terminology (J-ART).
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