The management of government purchases is an issue that plays a prominent role in the daily lives of Brazilian public managers. At the same time, it represents a challenge for issues related to legal aspects, efficiency, and administrative effectiveness. The general objective of the article is to evaluate the spending on the purchase of medicines through the minutes of registration of prices, within the scope of the Municipal Health Department of Manaus, with a budget cut from the years 2013 to 2015. For that, a case study of an exploratory nature was carried out. Data were collected through documentary research with the Protocol System of the secretariat. Subsequently, they were categorized and a database that enabled the analysis of the drug acquisition processes was generated. The results of the research indicate that the investment in the purchase of medicines is independent of the budget allocation and the efficiency of the drug procurement process is associated with the chain management of the entire acquisition process.