Effectiveness of Inventory Management System in Drug Inventory Control

Abstract

Background: Lampang Cancer Hospital faces issues such as the number of months for drug supply, high costs due to expired drugs, and a large number of drug items being out of stock. These issues reflect inefficient drug inventory control. Therefore, improving the inventory management system will increase the efficiency of drug inventory control, leading to a more effective and beneficial use of the hospital's budget.

Objectives: 1) To study the drug inventory control of Lampang Cancer Hospital. 2) To develop the internal vendor managed inventory (VMI) system for drug inventory control at Lampang Cancer Hospital. 3) To assess the effectiveness of VMI in drug inventory control at Lampang Cancer Hospital.

Method: This study is action research project consisting of 3 phases: 1) Study the drug inventory control system at Lampang Cancer Hospital. 2) Set up the internal VMI system in pilot sub-warehouses (partial VMI), where drug replenishment occurs from the main warehouse to sub-warehouses when the drug inventory level falls below the minimum stock level. 3) Implement the VMI system (full VMI). The effectiveness of the VMI system in drug inventory control is assessed based on the number of months of drug supply, the number of drug items being out of stock, and the cost of expired drugs. Descriptive statistics are used to compare these indicators before and after VMI implementation.

Results: The VMI system reduced the number of months of drug supply from 2.51 to 1.54 months. The cost of expired drugs decreased from 304,467.62 Baht to 129,676.25 Baht. The number of drug items being out of stock decreased from 18 to 10 during the full and partial VMI periods, respectively.

Conclusion: The VMI system, involving drug replenishment from the main warehouse to sub-warehouses, successfully reduced the number of months of drug supply and the cost of expired drugs. However, the number of drug items being out of stock before and after the internal VMI implementation cannot be directly compared. This is due to differences in data collection methods used in the two systems.