Pharmaceutical Medicine

, Volume 23, Issue 2, pp 65–75 | Cite as


An Overview of the Medical Dictionary for Regulatory Activities
  • Patricia Mozzicato
Review Article


The Medical Dictionary for Regulatory Activities (MedDRA) is a multi-axial, five-tiered hierarchical terminology used by regulatory authorities and the biopharmaceutical industry for the coding (classification) of clinical data in adverse event/adverse drug reaction (AE/ADR) reports. The terminology — developed by the International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH) — is maintained by an independent organization that distributes MedDRA via subscription. The activities of this organization — the Maintenance and Support Services Organization — are overseen by the MedDRA Management Board, which itself reports to the ICH Steering Committee.

MedDRAwas developed to overcome some of the limitations of previousAE/ADRcoding terminologies and to provide a single, multilingual resource for the classification of AE/ADRdata. Currently, MedDRA’s use is mandated for various types of regulatory reporting in the EU and Japan; it is widely used by the biopharmaceutical industry in all three ICH regions (US, EU and Japan). The US Food and Drug Administration has used MedDRA in its Adverse Event Reporting System for over a decade.

MedDRA provides a robust, vigorously maintained standard terminology for AE/ADR reporting with sufficient granularity of concepts and logical medical groupings within its hierarchy of terms. However, because of the size and specificity of MedDRA, as well as the organization of some of its groupings, retrieval and aggregation of coded AE/ADR data can sometimes present a challenge. Standardised MedDRA Queries (SMQs) have been developed in part to address this challenge. As of the time of writing, there are nearly 70 SMQ topics available to MedDRA users.

MedDRA’s use continues to expand 10 years after its official launch, driven primarily by the needs of — and input from — its user community.


Biopharmaceutical Industry Uppsala Monitoring Centre Individual Case Safety Report Periodic Safety Update Report Lower Level Term 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



The author is a member of the MedDRA Maintenance and Support Services Organization (MSSO) within Northrop Grumman Information Systems. MSSO does not own MedDRA but distributes it via subscription. MSSO also provides MedDRA-related services (e.g. training) to subscribers. No sources of funding were used to assist in the preparation of this article.


  1. 1.
    Introductory guide, MedDRA version 12.0, March 2009 [online]. Available to MedDRAsubscribers from URL: [Accessed 2009 Apr 1]Google Scholar
  2. 2.
    Mozzicato P. MedDRA — past and future. Regul Aff J Pharma 2006; 17 (12): 797–805Google Scholar
  3. 3.
    Wood KL. TheMedical Dictionary for Drug Regulatory Affairs (MEDDRA) project. Pharmacoepidemiol Drug Saf 1994; 3: 7–13CrossRefGoogle Scholar
  4. 4.
    Brown EG, Wood KL, Wood SM. The Medical Dictionary for Regulatory Activities (MedDRA). Drug Saf 1999; 20 (2): 109–17PubMedCrossRefGoogle Scholar
  5. 5.
    Cone M. Regulatory update: the long-awaited MedDRA has arrived! Good Clin Pract J 1999; 6 (1): 42–3Google Scholar
  6. 6.
    Huntley K, Veverka MJ, Golden M. The FDA’s medical dictionary for drug regulatory affairs alpha test. Drug Inf J 1995; 29 (4): 1133–43CrossRefGoogle Scholar
  7. 7.
    MedDRA term selection: points to consider, release 3.12, 1 April 2009 [online]. Available from URL: [Accessed 2009 Apr 1]
  8. 8.
    MedDRA data retrieval and presentation: points to consider, release 2.0, 1 April 2009 [online]. Available from URL: [Accessed 2009 Apr 1]
  9. 9.
    Zhao-Wong A, Rump E, Moraleda T, et al. Proposed terminology changes to facilitate the analysis of MedDRA-coded data. Drug Inf J 2006; 40: 291–303CrossRefGoogle Scholar
  10. 10.
    Brown EG. Effects of coding dictionary on signal generation: a consideration of the use of MedDRA compared with WHO-ART. Drug Saf 2002; 25 (6): 445–52PubMedCrossRefGoogle Scholar
  11. 11.
    Brown EG. Using MedDRA: implications for risk management. Drug Saf 2004; 27 (8): 591–602PubMedCrossRefGoogle Scholar
  12. 12.
    Fescharek R, Kübler J, Elsasser U, et al. Medical Dictionary for Regulatory Activities: data retrieval and presentation. Int J Pharm Med 2004; 18 (5): 259–69CrossRefGoogle Scholar
  13. 13.
    Tonéatti C, Saïdi Y, Meiffrédy V, et al. Experience using MedDRA for global events coding in HIV clinical trials. Contemp Clin Trials 2006; 27: 13–22PubMedCrossRefGoogle Scholar
  14. 14.
    Tremmel LT, Scarpone L. Using MedDRA for adverse events in cancer trials: experience, caveats, and advice. Drug Inf J 2001; 35: 845–52CrossRefGoogle Scholar
  15. 15.
    Brown EG, Douglas S. Tabulation and analysis of pharmacovigilance data using the Medical Dictionary for Regulatory Activities. Pharmacoepidemiol Drug Saf 2000; 9: 479–89CrossRefGoogle Scholar
  16. 16.
    Introductory guide for Standardised MedDRA Queries (SMQs) version 12.0, March 2009 [online]. Available to MedDRA subscribers from URL: [Accessed 2009 Apr 1]
  17. 17.
    Lindquist M. VigiBase, the WHO global ICSR database system: basic facts. Drug Inf J 2008; 42: 409–19Google Scholar

Copyright information

© Adis Data Information BV 2009

Authors and Affiliations

  1. 1.MedDRA Maintenance and Support Services OrganizationNorthrop Grumman Information SystemsChantillyUSA

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