(e.g., plasticizers, antioxidants) into the product matrix, affecting stability and safety.

Adsorption: Adsorption of drug molecules onto packaging surfaces, reducing drug concentration and efficacy.

Reaction: Chemical reactions between product constituents (e.g., APIs, excipients) and packaging materials, resulting in degradation or alteration of product properties.

2. Physical Interactions

Physical interactions may affect product appearance, formulation homogeneity, or container closure integrity:

• Aggregation: Aggregation or precipitation of product components due to interactions with packaging materials, leading to formulation instability.
• Adsorption Loss: Loss of volatile or low-molecular-weight components through adsorption onto packaging surfaces, impacting product potency.
• Permeation: Permeation of gases or moisture through packaging materials, affecting product stability and shelf life.

Approaches to Address Interactions

Stability studies employ various approaches to assess and mitigate interactions with packaging materials:

1. Compatibility Testing

Conduct compatibility studies to evaluate interactions between product formulations and packaging materials:

• Container Closure Systems: Assess compatibility with primary packaging materials (e.g., glass vials, plastic containers) and closure systems (e.g., seals, stoppers) under different storage conditions.
• Extractable/Leachable Studies: Identify and quantify potential leachable and extractable compounds from packaging materials that may migrate into the product.

2. Accelerated Aging

Subject packaged products to accelerated aging conditions to simulate long-term storage and assess interactions with packaging materials:

• Temperature and Humidity: Expose products to elevated temperature and humidity to accelerate degradation and evaluate packaging material compatibility.
• Light Exposure: Assess the impact of light exposure on product stability and potential interactions with packaging materials.

3. Real-Time Monitoring

Monitor product stability over real-time storage to assess long-term compatibility with packaging materials:

• Long-Term Stability: Evaluate changes in product attributes (e.g., potency, pH, appearance) over the intended shelf life to identify any adverse effects of packaging material interactions.
• Container Closure Integrity: Assess the integrity of container closure systems over time to ensure product protection and prevent interactions with external contaminants.

Conclusion

Stability studies are essential for assessing and mitigating potential interactions between pharmaceutical products and packaging materials. By employing compatibility testing, accelerated aging, and real-time monitoring approaches, manufacturers can ensure product integrity, stability, and safety throughout the product lifecycle. Addressing packaging material interactions not only enhances product quality but also supports regulatory compliance and patient safety.