The ability of a company to produce their products is essential for their survival in increasingly competitive markets. The present work proposes to minimize the production and inventory costs in order to optimize the production planning and control system decisions. The problem consists in understanding the benefits between anticipation inventory and employment levels and/or overtime in order to reach non-constant, time varying demand, considering fixed sale and production capacity. We create a mixed linear programming (MLP) model to support the decisions and adjustments in planning process and production management. This study applies to a specific retail product of a pharmaceutical industry and is implemented in the AIMMS modeling language. From the results, we can say that the implementation of this model is very useful and can help to find better solutions and improve the optimization of resources, which allows the company to anticipate its decisions and minimize the investments in inventories and costs of using overtime in terms of product families.