MedEx process free-text clinical records to recognize medication names and signature information, such as drug dose, frequency, route, and duration. It uses a context-free grammar and regular expression parsing to process free text clinical notes. After finding medication information, it maps to RxNorm and UMLS concepts at the most specific match it can find (e.g., medication name + strength would be preferred to medication name alone). It has been applied in 2009 i2b2 Medication Extraction challenge, placing second, and formally evaluated on Vanderbilt discharge summaries and clinical notes.
Executable versions available for Linux and Windows and Mac are below.
Download the latest version:
https://sbmi.uth.edu/ccb/resources/medex.htm
Key reference:
Xu H, Stenner SP, Doan S, Johnson KB, Waitman LR, Denny JC.MedEx: a medication information extraction system for clinical narratives.J Am Med Inform Assoc. 2010 Jan-Feb;17(1):19-24.