GLASS-AMU monitors Antimicrobial Use (AMU) at the national level. AMU data are estimates derived from aggregated data sources (ranging from macro-level, such as imports, distribution and sales, to micro-level, such as data on prescriptions, dispensing and insurance). Use and Consumption indicates the types and quantities of antimicrobials used in a specific setting over a specific period.

Enrolment of countries, territories and areas into the GLASS-AMU module was launched in December 2020. Enrolled countries are asked to provide three types of information: (1) a list of registered antimicrobial medicines; (2) the quantities of medicines used in the public and/or private sectors and in community and/or hospital settings for 1 year (January–December); and (3) related contextual information to clarify the data being sent to WHO and their relevance. According to its chosen methodology, WHO estimates AMU by using the international Anatomical Therapeutic Chemical classification and expresses the quantities of antimicrobials in defined daily doses for humans and metric tons (t) for comparison with data on consumption in animal health.

Data on AMU provide a basis for countries to understand the patterns and amount of antimicrobials used nationally and create appropriate policies, regulations and interventions for the optimal use of antimicrobials. By collecting data on AMR and AMU, GLASS permits the monitoring of trends for both surveillance data and provides insight into the drivers of AMR.