An Optimization Model for Hospitals Inventory Management in Pharmaceutical Supply Chain

Abstract

Afnaria, Tulus, Herman Mawengkang, Wiryanto

Pharmaceutical inventory problem which include the planning of pharmaceutical inventory is considered. The planning is based on the patient population which comes up as uncertain and vary through time. So that the demand becomes stochastic. Therefore, it is necessary to develop information to understand the relationship between patients arrivals, conditions, and demand for the pharmaceutical inventories. In Indonesia, the implementation of e-catalog system still causes some obstacles in terms of medicine availability. The direct appointment of the pharmaceutical factories and wholesalers has resulted production and distribution of drugs which are not optimal yet. What happens is the uncertainty in terms of the time order received (lead time) and the received quantity. Hence, the Hospital pharmacy (IFRS) must be able to respond to this by developing an inventory policy which are able to provide the sustainable pharmaceutical inventories. The objectives of this paper are to develop a multi-stage stochastic programming model to optimize the pharmaceutical inventory costs with uncertainty in demand, lead time and received quantity. This model assumes a continuous review policy, with a (Q, r) model for multi-products in one echelon pharmacy supply chain, i.e. a hospital. Stock out is overcome by backorder entirely, without considering loss sale.