Nanjing Kefeiping Shenghui Pharmaceutical Co., Ltd

Do you know how to correctly store unused ibuprofen, paracetamol, montmorillonite powder, or oral rehydration salts? Improper storage of pharmaceuticals not only leads to reduced or complete loss of efficacy, but may also cause toxic side effects that pose risks to your health. Below is a comprehensive guide to the standardized storage of common pharmaceutical dosage forms.

Tablets

Tablets are among the most stable pharmaceutical dosage forms. The active pharmaceutical ingredients (APIs) are encapsulated with excipients and protected by outer packaging, making them less prone to deterioration, with relatively lenient storage requirements. Their stability is mainly affected by environmental temperature, humidity, and light exposure.

For tablets in blister packs: Keep them in the original outer carton, and store in a cool, dry environment. Do not puncture the blister if the tablet is not to be used immediately.
For bottled tablets: Do not discard the desiccant after opening. Tighten the cap tightly after each use, return the bottle to its original outer carton, and store in a cool, dry place.
For scored tablets (e.g., levothyroxine sodium tablets): If you only need to take 1/4 or 1/2 a tablet at a time, it is recommended to split the tablet only when it is time to take the dose, rather than cutting all tablets in advance. The inner core of some tablets is highly hygroscopic and will deteriorate rapidly when exposed to moisture. Properly store the remaining split tablets and use them first; discard any tablets that are swollen or have absorbed moisture.

Injections

Liquid preparations generally have lower stability than solid dosage forms. APIs dissolved in liquid solvents are susceptible to precipitation, crystallization, and decomposition due to changes in solubility, pH, temperature, and light, which directly affect the safety and efficacy of the drug.

Most injections require protection from light, at minimum avoiding direct sunlight. Some drugs (e.g., mecobalamin for injection) may degrade even under normal indoor light, which is why medical staff use light-shielding cloths to cover the entire infusion set during clinical administration.

Capsules

Capsules are divided into hard capsules and soft capsules. Hard capsules contain powdered or granular solid APIs, while soft capsules contain oil-based APIs, both kept relatively stable under the protection of the capsule shell. The capsule shell is typically made of materials that dissolve in water, acid, or alkali to meet melting requirements in different physiological environments, and should generally be stored sealed at room temperature.

Capsule shells are highly sensitive to environmental humidity: they absorb moisture and soften in overly humid conditions, and crack and weather in overly dry environments, requiring moderate humidity for storage.
Similar to tablet storage requirements, bottled capsules are prone to sticking and agglomeration. Do not discard the desiccant, and tighten the cap tightly after each use.

Granules

Granules share similar storage principles with tablets, as tablets are typically compressed from granules. However, compared to tablets, granules have a larger surface area and are more susceptible to moisture absorption from the environment.

Granules must be stored sealed in a dry place to prevent moisture absorption, softening, caking, and other deterioration.

Oral Solutions

Like all liquid preparations, oral solutions are vulnerable to light exposure, which can alter the solubility of APIs or cause drug decomposition. They must be stored in a light-proof, airtight, and sealed manner.

Mixtures

TCM mixtures are generally concentrated extracts from medicinal herbs, which are prone to rancidity and deterioration at high temperatures. They should be stored sealed in a cool place.

Powders

Powders such as montmorillonite powder must be stored in a tightly closed, dry environment, as their fine powdered form makes them extremely hygroscopic. For powders containing special ingredients, stricter storage conditions apply, including airtight sealing with moisture-proof packaging materials.

Syrups

Syrups are liquid preparations with high sugar content, which are easily contaminated by microorganisms, especially in humid environments. They should be stored sealed, protected from light, and kept in a dry place.

Syrups are generally clear liquids; a small amount of precipitate after shaking is normal. However, if mold growth, sour taste, or air bubbles are observed, the product must be discarded immediately and must not be used.

Ophthalmic Preparations

This category includes eye drops, eye ointments (e.g., tobramycin eye drops, erythromycin eye ointment), which have strict sterility requirements as they come into direct contact with mucosal tissue. While most ophthalmic preparations contain bacteriostatic agents, these agents have a limited effective duration and antibacterial spectrum.

For safety, ophthalmic preparations must be stored sealed and protected from light. After opening, they can generally be used for a maximum of 4 weeks, and must be discarded after this period. Some eye drops have a shorter post-opening usage life; always refer to the specific product insert for detailed instructions.

Otic and Nasal Preparations

This category includes nasal drops, nasal sprays, and ear drops, with storage requirements similar to ophthalmic preparations but with slightly lower sterility standards. They should generally be stored in a tightly closed container, and must not be used for more than 4 weeks after opening.

Suppositories

Suppositories (e.g., paracetamol suppositories) melt and release APIs at normal human body temperature, meaning they will melt and deform if stored in an environment matching body temperature.

They must be stored tightly closed at temperatures below 30°C. In hot summer months, they can be stored in the refrigerator compartment.

Pills

TCM pills (e.g., Bupi Yichang Pills) are typically made with excipients such as starch and honey, making them prone to moisture absorption, mildew, and deterioration. They must be stored in a tightly sealed manner.

Ointments and Creams

These preparations use oil-based, emulsion, or water-soluble bases, which are prone to rancidity, hydrolysis, and delamination. They should generally be stored sealed and protected from light. Creams must be stored sealed at temperatures below 25°C, and must not be frozen.

Sprays and Aerosols

These preparations must be stored sealed and protected from light. Aerosol containers have higher internal pressure than atmospheric pressure; elevated temperatures will increase internal pressure, while hitting or impact may cause the container to rupture and explode.

Aerosols should generally be stored at temperatures not exceeding 20°C, and must be kept away from impact, dropping, or rough handling.

Gels

Gels are mostly topical preparations for dermatological use, which are prone to drying out or liquefaction. They must be stored sealed, protected from light, and protected from freezing.

Tinctures

Tinctures (e.g., opium tincture, iodine tincture) are liquid preparations extracted with ethanol, with inherent antiseptic properties, for both oral and external use. High temperatures will cause ethanol volatilization, so they must be stored sealed, protected from light, and kept in a cool place. Due to their ethanol content, they must be stored away from fire sources and open flames.

Colla Preparations

Colla preparations (e.g., donkey-hide gelatin) are mostly made from animal raw materials, often with added excipients such as sugar, oil, and wine. They must be stored tightly closed in a cool, dry place to prevent moisture absorption, heat exposure, mildew, softening, caking, and deterioration. Any product with an abnormal odor must not be consumed.

Note: Specific temperature requirements for each pharmaceutical product vary. Always refer to the storage instructions on the product insert for detailed guidance.

A Complete Guide to Proper Storage of Different Pharmaceutical Dosage Forms