Abstract

Pharmaceutical packaging serves as the first line of defense in preserving drug product quality, efficacy, and safety throughout the supply chain and shelf-life period. The selection of appropriate packaging materials and systems is critical to preventing degradation from environmental stressors including moisture, oxygen, light, and temperature fluctuations. This article examines the multifaceted relationship between packaging design and pharmaceutical stability, emphasizing the strategic importance of material selection, barrier properties, and container–closure integrity in maintaining product specifications. The discussion encompasses stability study design protocols aligned with International Council for Harmonisation guidelines, including long-term, intermediate, and accelerated testing conditions that simulate real-world storage scenarios. Analytical methodologies for stability-indicating evaluation are reviewed alongside common degradation pathways such as hydrolysis, oxidation, photodegradation, and physical instability. The interplay between packaging performance and environmental risk factors is analyzed through a quality-by-design framework that integrates material science with pharmaceutical development. Regulatory expectations for documentation, validation, and submission requirements are detailed with emphasis on global harmonization efforts. Emerging innovations in smart packaging technologies, active packaging systems, and sustainable materials are explored as drivers of future industry transformation. The article highlights persistent challenges including material compatibility testing, supply chain complexity, and the need to balance protective functionality with environmental responsibility. A comprehensive understanding of packaging–stability relationships is essential for ensuring patient safety, regulatory compliance, and commercial viability in an increasingly complex pharmaceutical landscape.