Stability of Refrigerated Drugs

Stability of Refrigerated Drugs

March 12, 2015

March 12, 2015 - When Proper Storage is Not Possible During Emergencies and Disasters

Power outages can accompany both natural and man-made disasters. In large-scale events where critical damage has occurred to the infrastructure, as seen with Hurricane Katrina in 2005, restoration of power may take weeks, even months. 

Preparedness plans for lengthy or widespread power outages often recommend keeping items such as water, non-perishable food items, and a 7 day supply of essential medications on hand1,2 .  It is vital to keep a supply life-sustaining medications during times of emergency; however, what if proper storage of these medications requires refrigeration? This component of disaster preparedness is often overlooked, though power outages are all too common during disasters.

Many refrigerated drug products can be stored at room temperatures, for variable periods of time. Nevertheless, common causes of power outages do not always facilitate optimal storage environments. Ice storms and heat waves are two common culprits of widespread outages. Ice storms can cause ice to buildup on both trees and power lines. When the weight of the ice becomes too heavy, tree limbs can fall and bring power lines down with them3.  During intense heat waves, the burden of lengthy and diffuse air-conditioning use can overwhelm power grids, causing blackouts4. Room temperature cannot be maintained in these situations. This reality raises another question; are refrigerated medications still viable if stored outside of room temperature?

Approximately 5 million Americans use insulin products to manage their diabetes5,6.  In 2014, over 1.9 million and 1.6 million prescriptions for the rheumatoid arthritis drugs Humira and Enbrel were filled in the United States7Over 5 million prescriptions were filled for the contraceptive ring Nuvaring7. The common denominator for all of these agents: proper storage includes refrigeration. These statistics show that maintaining the integrity of medications during disaster has been, and will continue to be a concern. 

Using a list of the top 200 prescription medications in the United States (by both retail sales and number of prescriptions filled)7, we have created a chart detailing the stability of common refrigerated drug products, as well as over the counter insulin products. The list includes proper storage data, allowable temperature excursions and the length of time such excursions are permitted, as well as contact information for product manufacturers to address questions that may arise on an individual basis. This provides an update for the most common refrigerated medicines dispensed in community pharmacies; practitioners may want to also consult the 2008 Pharmacist’s Letter Chart on Stability of Refrigerated and Frozen Drugs.

We hope this document will serve as a useful resource during times of disaster to ensure patients are using viable medications to manage their health conditions.

References:

  1. American Red Cross. Black Out/Power Outage Preparedness. Power Outage Safety. 2015.
  2. Centers for Disease Control and Prevention. Emergency Preparedness and Response. What You Need to Know When the Power Goes Out Unexpectedly.
  3. Duke Energy. Outage & Storm Information. Causes of Power Outages.
  4. Accu Weather, Inc. United States Weather News. Power Outages Attributed to Heat.
  5. Center for Disease Control. Diabetes Home. National Diabetes Fact Sheet, 2011.
  6. Center for Disease Control. National Diabetes Statistics Report, 2014. Estimates of Diabetes and Its Burden in the United States. 2014.
  7. Brooks M. Medscape Medical News. Top 100 Most Prescribed, Top-Selling Drugs . August 1, 2014.

Kerri-Lynn Conrad, PharmD Candidate

Kerri-Lynn is a fourth year student pharmacist at the University of Maryland School of Pharmacy. She conducted this research while completing an internship with Healthcare Ready, focusing on emergency preparedness in the community.