Stability: Back to the Basics - Part IV

Part IV: Stability and the Importance of Storage Conditions

In this five-part blog series, Alcami scientific experts, Russell Crothers and Adam Keisker, go “back to the basics” to examine the importance of stability in pharmaceuticals.


After expounding on the importance of efficacy and degradation in the previous blog, this fourth edition of the stability series will answer the most common questions people have about storing medicines and explain how storage plays a direct role on a product’s efficacy, along with which studies are used to measure efficacy.

Is it necessary to read the storage conditions listed on the label? Could where I keep my medicine damage it?

Yes! How medicine is stored influences its efficacy and safety. Remember to always follow the recommended storage conditions for the best use of a finished pharmaceutical product.

Heat, humidity and light are all responsible for degradation of products. Regulation committees, such as the Federal Drug and Food Administration (FDA), ensure that proper precautions are taken in order to maintain consumer safety. Establishing product integrity within different climate zones is essential because just the slightest change in temperature and humidity could affect medicines.

Stability storage and testing studies are performed to simulate climatic effects. The studies are based on where the products are going to be sold. Knowing all the ways a finished product or active pharmaceutical ingredients (APIs) could be affected by degradation is crucial in the storage of these products. From those studies, Alcami is able to establish a shelf life of the medicine, determine the best way to store the medicine and ultimately help ensure the safety of the consumer.

The International Conference on Harmonisation (ICH) distinguishes four worldwide climate zones as followed:

Zone I: temperate
Zone II: subtropical, with possible high humidity
Zone III: hot/dry
Zone IV: hot/humid

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Accelerated studies, or forced degradation, are used to predict the shelf life of a product. Scientists speed up the processes and rate of decomposition/degradation by increasing the temperature and/or humidity of environmental conditions for a brief period of time. These accelerations demonstrate the impact to the medicine if introduced to extreme conditions for a short period of time. Overall, this gives a general overview of the different properties of degradation including physical, chemical and microbiological.

Freeze-thaw studies determine whether the formula will remain stable under various conditions. Freezing is a common processing step used to maintain stability and quality of a drug substance during development and production of the medicine. The finished product/APIs are put through a series of rapid changes that could be encountered during shipping and handling of samples. The sample goes through a cycle of freezing conditions, usually around negative 20°C, and placed in higher temperature conditions, typically 25°C – 45°C, then tested. This cycle will occur over a span of a couple of days/weeks. The testing looks for any significant differences of the overall product throughout the entirety of the study.

Below is the ICH guidelines table for the different study parameters and the minimum time requirements needed to support the data. Please note that relative humidity is referred to as RH.



These parameters are set in place so pharmaceutical companies can establish strong data to support optimal storage conditions based on climate zones. Simulating these conditions and seeing how, over time, the product efficacy is affected is the purpose of stability.

In closing, remember to always properly store medicine in accordance with the manufacturer’s directions. Alcami is an industry leader in stability expertise and capabilities offering full ICH storage conditions, redundant facility capacity and any unique studies required like in-use, photostability and freeze/thaw.

Thank you for your interest in learning more about stability. Check back for the next post in this series, Part V: The Summation of Stability and Quality Attributes

Read Part III: Measuring Shelf Life-- Product Efficacy of API and Finished Drug Products

Read Part II: The Impact of Stability on the Safety of API and Drug Products

Read Part I: The Importance of Stability in the Evaluation of “Quality Attributes” of Pharmaceutical Drug Products

About the Authors

Russell Crothers is a leading authority for the generation, review, and edits of stability protocols at Alcami's St Louis site. He is responsible for the execution and management of the commercial and clinical development products for stability and maintains compliance with both ongoing and new regulatory requirements. His work as Lab Materials Support IV here is best showcased in his ability to streamline and digitize processes resulting in more efficient, precise stability services. He is the Power of Attorney for Controlled Substances at the Alcami St. Louis site. Russell graduated from Greenville College with a B.A. in Biology and has since joined the Alcami team in 2015.

Richard “Adam” Keisker is the Lead Sample Control Unit (SCU) Coordinator for Alcami’s St. Louis site. He oversees the coordination of analytical samples in a pharmaceutical testing environment, specifically the stability programs protocol approvals, storage, sets and release for analytical testing. Adam graduated from Lindenwood University with a B.A. in Chemistry with a concentration in forensics. 

Topics: Stability Blogs