Compared with bottled tablet medicine, blister packs have the greatest advantage of being easy to carry and can reduce contamination during drug handling and taking. However, as a patient who is on a regular basis, they need a large single dose, which makes the unit cost of the blister pack significantly higher than that of the bottled medicine.
The materials used in blister packaging are mainly PTP medicinal aluminum foil and plastic hard sheets. The medicinal aluminum foil is a sealing material sealed on a plastic hard sheet. It is made of hard industrial pure aluminum as a base material, and has the characteristics of non-toxic, corrosion-resistant, impervious, heat-resistant, moisture-proof, light-blocking and high-temperature sterilization. Plastic sheet materials are usually made of polyvinyl chloride (PVC), polyvinylidene chloride (PVDC) or composite materials. They have good barrier properties to water, steam and light.
Basic principles for selecting medicinal plastic hard sheets or composite materials
Ordinary tablet medicines, which are not required for moisture resistance, can be selected from polyvinyl chloride (PVC) sheets. PET hard sheets and PP hard sheets can be selected for medicines that have moisture and oxidation resistance requirements or that require a long shelf life. The composite hard sheets are polyvinyl chloride and polyvinylidene chloride composite sheets (PVC/PVDC) or polyvinyl chloride and polyethylene and polyvinylidene chloride (PVC/PE/PVDC) composite sheets. For oral liquid and suppository medicine, polyvinyl chloride and polyethylene composite sheets (PVC/PE) can be used.
General procedure for selecting a blister-packed rigid sheet material:
- According to the nature of the drug and the shelf life requirements, choose which polymer hard film to use. For details, consult a technical expert of the pharmaceutical packaging material manufacturing enterprise or conduct material testing. Fully consider the versatility of the equipment, the novelty of the appearance, and the lowest cost.
- Conduct a test on the machine to determine the suitability of the drug packaging materials for the equipment and the appearance of the product quality.
- Because of the different nature of various drugs, each drug needs to be tested for stability and compatibility.