The Read Codes Drug and Appliance dictionary (DAAD) covers medicinal products, appliances, specialist foods, reagents and dressings. The DAAD is part of the Clinical Terms (The Read Codes). Currently the DAAD is available in 4-byte and Version 2 Read Codes (also known as 5 byte).

The DAAD is updated and published every month in the TRUD subpack NHS_READDRUGS. To register download the subpack or for further information on release schedules visit the TRUD website. New/change requests for DAAD must be submitted via a change request form (PDF 29Kb).

Maintenance of the monthly Clinical Terms Version 3 (CTV3) DAAD ceased in July 2006. Biannually the release of the Read Codes contains CTV3 DAAD files which are the product of Version 2 DAAD concepts converted into CTV3 format. The data is provided to fulfil the superset principle and not intended for use in live clinical systems.

The Monthly Release Update Reports (which are released via TRUD) provide details of the additions and changes to the terming and coding of concepts and any technical update for 4-byte drugs and Read Version 2 drugs.