Optimal Temperature Conditions for Pharmacy Storage and Medication Efficacy

How do I know those pills I just bought that were sitting on the shelf are still good?

In this series about pharmaceutical temperature monitoring, we will discuss the best storage practices for pharmacies. In general, shelf-stable food products, including canned, bottled, and packaged goods, are designed to be stored below 85°F (30°C), ideally 70°F (21°C). But what about pharmaceuticals stored at ambient store temperatures, those bottles of pills, capsules, and tablets sitting there on the shelf?

When pharmaceutical companies develop medications, they examine many factors such as effective dose, side effects, how it needs to be administered (orally, injection, transdermal, etc.), effects of overdose, safety, and efficacy. A significant amount of time is spent understanding the effects of storage on the preparation. These studies will determine if the medication is stable at room temperature, needs refrigeration, or needs to be frozen, as well as degradation during such storage. How this applies to pharmacies takes us on a journey.

Temperature Regulations for Storing Medication

Fortunately, room-temperature pharmaceutical storage is subject to regulation in the U.S. The U.S. Food and Drug Administration (FDA) regulations in CFR 21 (CFR2111) define stability testing for pharmaceutical manufacturers and note testing shall be used in determining appropriate storage conditions and expiration dates. (Section 211.166) In 21CFR205.50 the FDA guidelines for State Licensing of Wholesale Prescription Drug Distributors state that all facilities where prescription drugs are stored, warehoused, handled, marketed, or displayed are to be maintained properly. FDA wording follows in italics.

Download our brochure now to find out how SmartSense drives increased quality, compliance, and operational efficiency in pharmacies.

(c) Storage. All prescription drugs shall be stored at appropriate temperatures and under appropriate conditions in accordance with requirements, if any, in the labeling of such drugs, or with requirements in the current edition of an official compendium, such as the United States Pharmacopeia/National Formulary (USP/NF). 

(1) If no storage requirements are established for a prescription drug, the drug may be held at "controlled" room temperature, as defined in an official compendium, to help ensure that its identity, strength, quality, and purity are not adversely affected.

(2) Appropriate manual, electromechanical, or electronic temperature and humidity recording equipment, devices, and/or logs shall be utilized to document the proper storage of prescription drugs.

(3) The record-keeping requirements in paragraph (f) of this section shall be followed for all stored drugs.

FDA Guidelines for Refrigerated Medication in Pharmacies

Pharmacy regulations are issued by each state. In general they refer to or mirror the FDA guidelines which often refer to manufacturer’s guidelines. In Massachusetts for example, 247CMR9.00, section 901(5) states, While on duty, a pharmacist shall be responsible for proper preservation and security of all drugs in the pharmacy or pharmacy department, including the proper refrigeration and storage of said drugs. Massachusetts 247CMR9.00 for wholesale druggists, section 7.04(3) states,

All prescriptions shall be stored at appropriate temperatures and under appropriate conditions in accordance with requirements, if any, in the labeling of such drugs, or with requirements in the current edition of an official compendium such as the United States Pharmacopoeia/National Formulary (USP/NF).

(b) If no storage requirements are established for a prescription drug, the drug may be held at "controlled" room temperature, as defined in an official compendium, to help ensure that its identity, strength, quality, and purity are not adversely affected. 

(c) appropriate manual, electromechanical, or electronic temperature and humidity recording equipment, devices, and/or logs shall be utilized to document proper storage of prescription drugs.

(d) The record-keeping temperature requirements in 247 CMR 7.04(6) shall be followed for all stored drugs.

What this boils down to is the manufacturer’s label defines the requirement. The good news is that manufacturers do publish storage conditions for drugs stored at room temperature which is defined by the U.S. Pharmacopeia as between 68-77°F (20-25°C). Take for example a common high blood pressure medication, lisinopril, also sold as Prinivil, Tensopril, Zestril, or Hipril. The image below (Figure 2) is from the information sheet included with Zestril, AstraZeneca’s version of lisinopril, and posted on the FDA’s site. The data sheet notes the recommended storage conditions for Zestril tablets: Store at controlled room temperature, 20-25ºC (68-77ºF)[see USP]. Protect from moisture, freezing, and excessive heat. Dispense in a tight container. Note the reference to USP guidelines.

How to Monitor and Control Pharmacy Storage Conditions

More importantly, note the datasheet calls for a controlled room temperature. If I walk into a pharmacy that feels hot, I know the drugs stored there are likely to be degrading faster than expected. Fortunately, many pharmacies keep limited quantities of any particular drug, so drugs that are in constant demand like lisinopril are not likely to be sufficiently degraded if exposed to elevated temperatures for short periods, Of greater concern are medications that have slow turnover. Pharmacies that regularly run hot can potentially compromise the efficacy of such drugs.

Figure 2. AstraZeneca Zestril (lisinopril) storage conditions, from datasheet. Link to Form

Pharmacy managers and pharmacists are responsible to keep the drugs under their management within recommended storage conditions. Automatic temperature and humidity monitoring systems can provide warnings and alarms when temperatures exceed or fall below the recommended range, providing pharmacy managers and pharmacists with the information needed to correct the issue when problems occur.

Many have tasted wine that has been exposed to elevated temperatures for a period of time, vinegar comes to mind. Likewise, many have tasted bagged popcorn that has been exposed to elevated humidity for a long period of time. If I enter a store or pharmacy that is very warm and humid, I generally will not purchase items where the quality can be compromised. The same goes for prescription and OTC medications. 

SmartSense Temperature Monitoring for Pharmacy Managers

Pharmacy managers, operators, and pharmacists are responsible for maintaining an environment that keeps prescription medications within recommended temperatures. Pharmacies that let customer discomfort be the warning that things are too hot or humid are likely to see these customers disappear if the condition persists. Proactive programs to maintain ambient store temperature within the manufacturer’s specification are good for patient outcomes and good for business.