A short guide to primary pharmaceutical packaging
Compared to other types, primary pharmaceutical packaging is certainly one of the most complex and regulated. In fact, its role is not limited to containing and facilitating the transport of goods, but must also guarantee the integrity of extremely delicate products such as medicines, to protect patients’ health.
In contrast to secondary packaging, i.e. the outer packaging of the medicine which is often a cardboard box, primary packaging refers to the packaging that comes into direct contact with the medicine (e.g. ampoules for injectable solutions, bottles for syrups, etc.) and therefore plays an essential role in its preservation and how the patient uses it.
The types of pharmaceutical primary packaging
An initial classification of the types of primary packaging available on the market can be made on the basis of the pharmaceutical form and administration route. Generally speaking, we will have different packaging solutions for liquid injectables, liquid and solid oral medicines, liquid and semi-solid formulations for topical, ophthalmic and nasal use.
Medicinal product containers: bottles, pill bottles and dispensers in glass and plastic
The materials used for primary pharmaceutical packaging are mainly glass and plastic.
Glass is chosen for its excellent chemical and mechanical properties, which allow for high stability, strength and transparency. Depending on its level of hydrolytic resistance, i.e. its resistance to releasing soluble mineral substances from the surface into the contents, glass is classified into:
- Type I also known as borosilicate, it is the most stable and resistant, and is ideal for more delicate medicines such as injectables;
- Type II and Type III, that are sodium-calcium based, perform well and are suitable for all solutions, from parenteral to oral.
The pillbox and plastic bottle family is a large one and allows great flexibility in terms of formats and customisation. The main plastics used in the pharmaceutical field are: PET, LDPE, HDPE, PP, PE, COC and PEN. The choice of the most suitable polymer is always only made following thorough assessments of the degree of compatibility between drug and container. To ensure protection of the most sensitive drugs, special additives can be added to minimise the effect of moisture and enhance UV protection.
Thanks to constant research into sustainable materials there are more and more environmentally friendly solutions available on the market, made from bio-plastics, recycled plastics or from CO2 recovery.
Pharmaceutical packaging closures: plastic, aluminium and rubber caps
For a primary pharmaceutical packaging solution to be considered complete, the right closure must be matched to the container.
Plastic capsules are the most commonly used for liquid and solid oral applications. In addition to the material, the degree of security also determines their classification into:
- “screw top” closures: easy to open, more suitable for non-pharmaceutical products;
- TE closures: equipped with a tamper-evident ring;
- “Child-Proof' closures: with a locking mechanism that makes opening more difficult, preventing access to the contents by children.
Capsules are often supplemented by dispensing systems such as vertical droppers or suction pipettes, which allow liquid drugs to be dispensed with extreme precision.
Included in the accessories that can be incorporated into the closures, specific components are also available to increase the level of insulation and protection of the drug from external agents. This is the case with liners thin discs that are placed between the capsule and the bottle to provide extra protection. These can come in different shapes and thicknesses (standard, flat, expanded, induction, for droppers). Another example are capsules with silica gel which increase protection against moisture.
Lastly, there are rubber stoppers used exclusively for vials and bottles for parenteral use, i.e. for injectable and infusion medicines. Because of their direct interaction with the drug, they differ from ordinary rubber products for industrial or domestic use, and are manufactured in a controlled environment, called a clean room. Great attention is also paid to the density of the material, which must be easy to pierce with the needle and at the same time resistant to ensure a safe withdrawal of the liquid. To increase protection and safety, the rubber stoppers are then in turn sealed by aluminium ferrules.
Medical devices: drug delivery and dispensing accessories
In addition to primary pharmaceutical packaging, there is another category of products that comes into direct contact with the medicine and must therefore also be subject to a strict regulatory process. These are all the medical devices used for the administration and dosing of drugs, such as measuring cups, teaspoons or droppers.
Usually these accessories are made of plastic, but there may be variations depending on the specific requirements for storage, insulation and protection of the product. In addition to material conformity, these systems are developed to guarantee the highest levels of precision, an indispensable element for the correct delivery of prescriptions. At the same time, they must ensure intuitive and safe use, preventing breakage or accidental ingestion of parts.
A short guide to primary pharmaceutical packaging
The primary packaging of medicines must fit the product perfectly, so as to ensure its integrity at all times, to prevent contamination by external agents and to not have any characteristics that may alter it in any way.
To ensure this, the packaging manufacturer must comply with regulatory requirements and meet quality standards which are reflected in the International Pharmacopoeia. All products are manufactured following very strict procedures, with numerous pre-tests, as well as repeated in-line and finished product checks.
Strict regulations also govern drug administration accessories. These,according to the recent definition in Regulation (EU) 2017/745, fall under the category of medical devices and as such must comply with specific safety requirements, checked and certified by notified bodies.
Finally, another important reference standard is the UNI EN ISO 15378: 2018, which integrates GMP (Good Manufacturing Practice) requirements into the pharmaceutical packaging production process. It imposes precise requirements at all stages of the production process: from design to manufacturing and logistics.