GPI vs. GSN

Medi-Span and First Databank (FDB) are two of the most widely utilized drug compendia publishers.  Both publishers include drug attributes and pricing values.  Each publisher also has a unique, proprietary drug identifier that groups products with the same active ingredient, strength, route, and dosage form.

The Generic Product Identifier (GPI) from Medi-Span is 14 characters made up of 7 couplets.  FDB has the Generic Sequence Number (GSN) also known as the Clinical Formulation ID or formerly as GCN Sequence Number (GCN Seq No), which is 6 digits in length.  FDB also has the GCN (Formulation ID) which is 5 digits, but the GSN is more detailed and will be the focus of this review.

This table highlights some of the differences between the GPI and GSN.

Attribute GPI GSN
Hierarchy Yes No (see NOTE below)
Regular changes Yes Few to none
Value Limitations Dosage form couplet N/A
Therapeutic Classifications 1 per GPI No (see NOTE below)

The GPI is setup as a hierarchy, which allows groupings at less specific levels than the active ingredient, strength, route, and dosage form.  Here is an example of the GPI hierarchy for Nortriptyline HCL 10mg capsules:

GPI Coding Example
58- Drug Group Antidepressants
58-20- Drug Class Tricyclic agents
58-20-00 Drug sub-class Tricyclic agents
58-20-00-60 Drug name Nortriptyline
58-20-00-60-10 Drug name extension Nortriptyline HCL
58-20-00-60-10-01 Dosage form Nortriptyline HCL Capsule
58-20-00-60-10-01-05 Strength Nortriptyline HCL Capsule 10mg

GPIs may change at any of the hierarchy levels.  Each couplet is limited because currently only numbers are used, although letters will be added July 1, 2013 to expand their capabilities.  The dosage form couplet at position 11 and 12 of the GPI will be the first to be expanded with the use of letters.  A 14 character GPI resides in a single therapeutic classification due to the hierarchy.

The GSN does not utilize a hierarchy.  This reduces the need for a GSN to change because there is not a defined sequence to the numbers.  The individual digits of the GSN do not have meaning, so the GSN is only limited in its entirety.

NOTE: The Hierarchal Ingredient Code (HIC) and Enhanced Therapeutic Classification System (ETC) are the separate identifiers that FDB publishes to achieve groupings at the organ system, therapeutic class and subclass, and active ingredient (with and without the salt).

There is no right or wrong answer on which proprietary identifier to use.  The GPI has several built-in features but requires maintenance.  The GSN requires the use of additional identifiers but with less maintenance.  PHSI has extensive experience with both drug compendia and their respective identifiers as depicted here and here.

Contact PHSI with your questions about the Medi-Span GPI and FDB GSN today!

8 responses to “GPI vs. GSN”

  1. Priscila says:

    Does anyone know if there are other options out there besides Medispan or FDB? I came across another vendor – CIMS, unfortunately that does not satisfy our language specs (French). Any help is very much appreciated. Thanks!!

    • Alan Sekula says:

      Priscila,
      Thanks for reading our blog posts and sending your question.

      Two other databases to consider are Cerner Multum (www.multum.com) and Gold Standard (http://www.goldstandard.com/) . We would be glad to pass any additional information along if any other reader would like to weigh in on your request.

      We encourage you to keep reading our posts and please don’t hesitate to send further questions or comments.

      Thanks again,
      The PHSI Team

  2. Caroline says:

    Where can I find a list of the GPI numbers?

    • Alan Sekula says:

      Caroline,
      Thanks for reading our blog posts and sending your question. GPI is a proprietary hierarchical therapeutic classification scheme from Medi-Span. You must be a subscriber to Medi-Span to access GPI numbers. Please follow this link to learn more http://www.wolterskluwercdi.com/drug-data/why-medispan/

      We encourage you to keep reading our posts and please don’t hesitate to send further questions or comments.

      Thanks again,
      The PHSI Team

  3. Juan Lopez says:

    I read this very informative article you have on GPI vs GSN. As of this writing, has anything change on the article and is it still valid. I have been task to give pros’ and cons’ of the two products.

    • Alan Sekula says:

      Juan,

      Thanks for reading our blog and providing your comment! The descriptions and comparisons for Medi-Span’s GPI and First Databank’s GSN remain valid today. The only update we would recommend you also check out is on the Medi-Span dosage form (6th couplet comprising the 11th and 12th characters) found here: http://phsirx.com/blog/new-medispan-dosage-forms . Just like you are tasked with, there are pros and cons that need to be evaluated based on your needs. We hope this helps!

      Thanks again,
      The PHSI Team

  4. Dave Belle says:

    Do either of these identifiers take into account package size (10ml vial vs 5ml vial) ?

    • Alan Sekula says:

      Dave,

      Thanks for reading our blog and providing your comment! The GPI from Medi-Span and the GSN from FDB do not take into account the package size (10ml vs 5ml vial). Medi-Span does offer an additional identifier called the GPPC (Generic Product Packaging Code). The GPPC is the equivalent of the GPI plus the package size. The GPPC would group all nortriptyline 10mg 100 count bottles into one GPPC while the nortriptyline 10mg 500 count bottles would be in a unique GPPC. We are do not believe that FDB offers a similar identifier. PHSI welcomes the opportunity to work with you on this challenge to help you use the data to meet your needs.

      We encourage you to keep reading our posts and please don’t hesitate to send further questions or comments.

      Thanks again,
      The PHSI Team

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