Health products policy and standards
Our team provides authoritative guidance and standards on quality, safety and efficacy of health products and supports countries to formulate evidence-based policies and ensure good practice throughout the value chain.
INN stems
To select an appropriate stem, please read carefully
5 November 2007
Guidance on the establishment of new INN stems - 20070611
Guidance for INN applicants with regard to the establishment of new INN stems
All about existing stems and pre-stems can be downloaded here:
14 October 2024
Use of stems in the selection of International Nonproprietary Names (INN) for pharmaceutical...
The document “Use of stems in the selection of International Nonproprietary Names (INN) for pharmaceutical substances” is intended primarily for persons...
19 June 2025
INN Stem Book Addendum 202506-2024
The document "Use of stems in the selection of International Nonproprietary Names (INN) for pharmaceutical substances" is intended primarily for persons...
The step before the adoption of an INN stem by the INN Expert Group is to publish them as a pre-stem in order to collect possible issues.