MedDRA - It is the Language of Global Drug Safety
In pharmacovigilance and regulatory science, clear, consistent medical terminology is critical. That’s where MedDRA (Medical Dictionary for Regulatory Activities) comes in.
It’s a globally standardized coding system that enables accurate and reliable tracking of:
Adverse drug reactions (ADRs)
Medical history & indications
Drug-device interactions
Clinical trial findings
Why is MedDRA important?
It ensures that safety data from around the world can be compared, analyzed, and understood.
It supports signal detection, benefit-risk assessments, and regulatory submissions to authorities like the FDA, EMA, and PMDA.
It’s a required standard in many databases: FAERS, EudraVigilance, VigiBase.
MedDRA Hierarchy: From General to Specific
SOC – System Organ Class
Broad category (e.g., Cardiac disorders)
HLGT – High-Level Group Term
Groups HLTs by function or anatomy
HLT – High-Level Term
Clusters of related PTs
PT – Preferred Term
Standard term used for data analysis (e.g., Palpitations)
LLT – Lowest Level Term
Verbatim terms from reporters (e.g., Heart fluttering)
Example:
A patient reports “feeling faint” →
LLT: Fainting spell
PT: Syncope
HLT: Neurological disorders NEC
SOC: Nervous system disorders
This structure helps safety professionals track everything from broad disease categories to specific symptoms or events.
MedDRA in Action
A patient says: “I felt dizzy and had chest tightness.”
With MedDRA, these symptoms get coded precisely as:
MedDRA coding:
•PT: Dyspnoea
•PT: Chest pain
•Helps global analysis of similar symptoms
What Are SMQs in MedDRA?
SMQs = Standardised MedDRA Queries
These are pre-defined groupings of MedDRA terms used to retrieve cases related to a medical condition or area of interest (e.g., liver injury, anaphylaxis, QT prolongation).
SMQs improve signal detection by pulling together relevant PTs that may otherwise be missed in individual coding.
Key Applications of MedDRA:
ICSR (Individual Case Safety Report) coding
Periodic safety update reports (PSURs)
Standardized MedDRA Queries (SMQs) for signal detection
Coding in clinical trial adverse events
Where Is MedDRA Used?
- ICSRs in safety databases like FAERS, EudraVigilance, VigiBase
- Clinical trial data (CTDs, DSURs, IBs)
- Post-marketing surveillance
- Risk management plans (RMPs)
- Safety labeling and communication
- Medical writing (for adverse event listings, summaries, narratives)