The pharmaceutical sector in Latin America, particularly in Peru, has seen significant growth, with small and medium-sized enterprises (SMEs) playing a crucial role in the supply of essential medications and health products. Despite their importance, these SMEs face considerable challenges, particularly in inventory management and logistics, which have not been sufficiently addressed in existing research. The sector urgently needs solutions to issues such as inadequate storage systems, inefficient inventory management, and the high incidence of product obsolescence, which directly impact the efficiency and competitiveness of these companies. This study proposed a Lean Storage Model specifically designed for pharmaceutical marketing SMEs in Peru, incorporating Lean Manufacturing tools such as 5S, standardized work, and Kanban. The model was applied in a case study of a Peruvian SME, leading to measurable improvements, including a 47% reduction in picking process time, a 41% decrease in product obsolescence, and a 10.78% increase in service level, aligning it with industry standards. These results highlight the model's potential to enhance operational efficiency, reduce waste, and improve overall competitiveness in the pharmaceutical sector. The study's findings contribute to the academic discourse on Lean Manufacturing in SMEs and provide a practical framework for similar companies facing comparable challenges. Further research is encouraged to explore additional Lean tools and their application in other sectors.