The document discusses drug supply management and explains key concepts such as:
1) The drug management cycle includes selection, quantification, procurement, distribution and use of drugs. Accurate quantification is important to avoid shortages or overstock.
2) The essential medicines concept focuses on a limited selection of carefully chosen medicines to improve health outcomes and reduce costs.
3) Drug quantification methods include consumption-based, morbidity-based, and proxy consumption approaches. Consumption is preferred when data is reliable.