Temperature is Critical for Safe, Effective Refrigerated Drug Storage

Refrigerated medications need special care; guidelines and regulations help with direction

In the previous piece we looked at room temperature storage of pharmaceuticals. Many of us are familiar with the requirements of the prescriptions we have filled and take home. Similar information can be found on pharmacy websites. For example, the CVS website FAQs provides the following information for Lisinopril a common high blood pressure medication: Link to Source

 Where should I keep my medicine? (Non-Refrigerated Drugs)

• Keep out of the reach of children.
• Store at room temperature between 15°C and 30°C (59°F and 86°F). Protect from moisture. Keep container tightly closed. Throw away any unused medicine after the expiration date.

Most households maintain these conditions, therefore drug effectiveness and safety are maintained. But what about refrigerated medications or those stored in a freezer in the pharmacy? These require a close look; particularly since regulators often review refrigerated and frozen drug storage conditions during audits.

What types of drugs require refrigeration? Again, the CVS website is helpful here and provides a list of fifty common prescription medications that require refrigeration. The list includes commonly recognized generic and brand names such as insulin, Cipro and Enbrel. Most of those listed are solutions, suspensions, vials or capsules.

While these drugs are for use at home, medical offices and pharmacies store medications to be administered on site such as vaccines. Fortunately the US Center for Disease Control (CDC) has published extensively on safe storage and handling of vaccines for their Vaccines For Children (VFC) program. The CDC's Vaccine Storage and Handling Toolkit (Link to Source) specifies storage temperature between 2°C and 8°C (35°F and 46°F). This range is also commonly used for medications other than vaccines which makes a pharmacist’s job easier.

To ensure the vaccine’s efficacy is maintained, VFC providers must maintain a log of at least temperature readings each day using a certified thermometer. While many pharmacies and medical offices use manual reading and recording, many more are deploying temperature monitoring devices that record temperatures automatically and continuously, even when the store is closed and no personnel are present. Some US states require such devices; check local regulations to determine the requirements in your state. Generally a manual reading and logging is also required even where automatic monitors are deployed, most likely so that staff members will be aware of any out of range conditions since many automatic devices log the data but do not provide warnings or alarms when temperatures are out of range.

Pharmacies, hospitals, and medical practices participating in the VFC program are required to take readings with a certified thermometer twice per day, in the morning and evening. Readings are manually recorded on temperature logs. These logs are sent monthly to the CDC for review and action when needed. Some states require automatic temperature monitoring equipment to insure that there are no gaps in temperature logs. Automatic temperature monitoring equipment can be configured to record temperatures every minute, or in any interval. Commonly intervals of 15 minutes are set for pharmaceutical monitoring. Data is sent to state health departments monthly.

In some devices data logs are manually downloaded to a computer hard drive by USB weekly or monthly. Monitoring with such devices with intervals less than 15 minutes can fill up data storage capacity and exceed limits on many devices. Wi-Fi temperature monitors may be able to be configured to automatically download data to a networked computer negating the need to manually download. Wi-Fi and wireless temperature monitoring devices rely on the stability and reliability of the local IT network and electric power grid, and when these services are interrupted, not an uncommon experience, temperature readings can be lost.

To minimize reliance on manual operation, IT networks and electrical power, leading pharmacies have begun to adopt cellular temperature monitors that communicate when IT networks and power supplies are interrupted. Data is sent via major cellular providers to reliable, redundant data centers, ensuring data integrity. Pharmacists can access data via a web browser and set password controlled temperature alert and alarm limits. Some devices provide email, text, and voice message alert and alarm messages to insure harmful conditions do not go unnoticed, on Saturday at 2:00 AM for example. Such an approach represent the leading edge of fault-tolerant operation.