Can HPMC empty capsules be left unused for a long time?

HPMC empty capsules can be left unused for a long time, but they need to be stored under appropriate conditions. Specifically, the following factors need to be noted:
1. Storage conditions: HPMC empty capsules should be stored in a dry, cool, and well ventilated place, avoiding direct exposure to high humidity, high temperature, or strong light. Long term storage in an inappropriate environment may affect the quality and performance of the capsules.
2. Humidity control: HPMC capsules are sensitive to humidity. High humidity environments can cause capsules to absorb moisture, leading to softening or expansion and reducing their stability. Therefore, when storing, it is advisable to maintain the environmental humidity within an appropriate range (usually 30% -50%).
3. Temperature control: The performance of HPMC capsules will be affected by temperature changes. Excessive temperature may cause the capsule to become brittle or dissolve, while excessively low temperature may affect the mechanical strength of the capsule. The storage temperature should be controlled at room temperature to avoid extreme temperature changes.
4. Container sealing: To prevent air and moisture from entering, sealed packaging such as aluminum foil bags or sealed plastic bags can be used to store HPMC capsules. This can effectively extend the shelf life of the capsule, keeping it dry and intact.
5. Shelf life: Although HPMC empty capsules have a longer shelf life, their physical properties (such as brittleness) may change after prolonged storage. Therefore, when used after long-term storage, it is best to check the condition of the capsules to ensure that they have not deteriorated or been damaged.