The stability of an Active Pharmaceutical Ingredient (API) is influenced by which factors?

The stability of an Active Pharmaceutical Ingredient (API) is significantly influenced by environmental factors such as humidity, light, and temperature.

Humidity affects stability because high moisture content can lead to hydrolytic degradation of the API, particularly for compounds sensitive to water. This moisture can promote reactions that compromise the integrity of the drug formulation.

Light exposure is another critical factor, especially for APIs that are photosensitive. Ultraviolet or visible light can induce changes in molecular structure, leading to degradation or loss of potency. Protecting photosensitive drugs from light is essential to ensuring their stability over time.

Temperature also plays a crucial role in stability. Elevated temperatures can increase the rate of chemical reactions, including degradation pathways that may reduce the efficacy of the API. Conversely, lower temperatures can slow down these reactions but may also lead to other stability issues like crystallization or phase separation.

Each of these factors interacts to influence the overall stability and shelf life of pharmaceutical formulations. Therefore, understanding and controlling humidity, light, and temperature is vital in the storage and formulation of API to maintain drug stability and efficacy.