Pharmaceutics PTCB Test Prep

Storage Requirements for Medicines!

Jul 15th, 2020
storage requirements for medicines

Medicine Storage Requirements

Pharmacy technicians are expected to have a thorough knowledge of storage requirements for medicines. Not all medicines are stored in the same way. Some medicines have different storage instructions – and it is those instructions that we review here.

Technicians should understand the importance of accurate storage. For example, some drugs are light-sensitive whereas other drugs are temperature sensitive. If the drug is exposed to its vulnerability for a prolonged period, it can degrade the effectiveness of the medicine. In some cases, the medicine can become hazardous.

Pharmacy technicians must have an appreciation of correct storage requirements and to identify how a medicine should be stored and whether a medicine has been incorrectly stored. Most medicines are stored at room temperature – between 59-86 degrees F (or 15-30 degrees C).

However, some drugs must be refrigerated or frozen (see table below). Not many drugs are frozen these days. This is mostly limited to some vaccines.

Consequences of Incorrect Storage

Medicines stored outside recommended storage requirements face several possible consequences.

For example – some drugs, such as suppositories, can melt. Incorrect storage can also lead to a reduced shelf-life, meaning the drug is effective within a much narrower range. Third, some drugs may suffer only a partial loss of effectiveness whereas incorrect storage can lead other drugs to a complete loss of effectiveness. Even if incorrectly stored medicine is not harmful itself to patients, it can lead to a significant loss of clinical effectiveness which indirectly damages the patient’s health outcomes. For some medicines, this can prove profoundly serious for the patient.

Medicines should always be stored in original packaging and stored in the recommended zone – whether this is stored away from sunlight or whether to refrigerate the medicine. Incorrectly stored medicines can undergo both physical and chemical changes.

This can lead to effects such as:

  • Alterations to how the medicine tastes
  • Alterations to how the medicine appears
  • Alterations to how the medicine smells

The chemical structure of the medicine may also change. An otherwise liquid medicine may become thicker, for example, leading to incorrect dosing. Medicines that are light-sensitive can degrade when exposed to light. For this reason, many tablets, for example, are stored in amber medicine bottles (see image above)

Similarly, chemical incompatibilities can lead to effervescence, drug precipitation from its diluent or vehicle, decomposition, and – in rare cases – explosions. Let us not forget that medicines are – at the most fundamental level – chemical entities and so, in some cases, there carries a legitimate risk of explosions. This is more likely, for instance, in medicines exposed to high temperatures for a prolonged period.

Moisture can become a problem, too. Like light-sensitive drugs, some medicines are sensitive to moisture and, because of the chemical nature of moisture itself, this can lead to chemical incompatibilities and loss of drug potency.

Below, we have put together a table of special storage requirements for some of the most used medicines.

Note that, for the PTCB examination, students are not required to memorize all drug storage directions. Instead, candidates must have a working knowledge of the importance of storage instructions, how to identify incorrectly stored medicines, and the type of damage that can result when medicines are improperly stored.

Special Storage Requirements – Examples

Cyclosporine capsulesLight sensitive
DabigatranMoisture sensitive
EtanerceptLight sensitive
Nitroglycerin sublingual tabletsBoth light and moisture sensitive
Oxcarbazepine oral solutionLight sensitive
Ritonavir capsulesBoth light and moisture sensitive
GolimumabLight sensitive
DipyridamoleMoisture sensitive

Commonly Refrigerated Medicines
AugmentinAmoxicillin / clavulanic acid
HumalogInsulin lispro
LantusInsulin glargine
LevemirInsulin detemir
AvonexInterferon beta-1a

VaccineFunctionStorage Requirements
Engerix-BHepatitis BRefrigeration
HavrixHepatitis ARefrigeration
MMRV: ProQuadMeasles
ZostavaxHerpes zoster
VAR: VARIVAXVaricella (chickenpox)Freezer