Fundamentals of stability testing

Synopsis The principles on which stability tests are based are reviewed. The need to differentiate between product stability and product-container compatibility is emphasized. Recognition of this distinction is fundamental to the efficient organisation and execution of stability tests. Attention is also drawn to the desirability of having for every product a release specification with which it must comply when manufactured and a broader check specification with which it must comply throughout its shelf-life. Test methods and the interpretation of the data accrued throughout a test are also discussed. It is concluded that stability tests should not be conducted in accordance with a standardized routine pattern but that the objectives of each test should be defined and the test designed to achieve those objectives in the most efficient way.