Pharmacopoeias: the tests a plastic passes before it holds a medicine
Before it touches a medicine, a plastic material has already been through a series of tests described in the pharmacopoeias. These texts do not say which bottle to choose. They say what has to be proven.
By Tecmom editorial team · 2 min read
What a pharmacopoeia is
A pharmacopoeia is an official collection of quality standards for medicines and what surrounds them. In Europe it is the European Pharmacopoeia, published by the European Directorate for the Quality of Medicines, EDQM. In the United States it is the USP. Japan has its own.
For packaging, the European Pharmacopoeia devotes one chapter to the materials used to make containers, 3.1, and another to the containers themselves, 3.2. It includes monographs for polyolefins, polyethylene, polypropylene and PET for non-parenteral preparations.
What the tests check
The tests first address the material's identity, often by infrared spectroscopy: checking that it is what it is believed to be. Then come additives, such as antioxidants, whose nature and content are limited, and the substances that can pass into an extraction solution: metals, oxidisable matter, acidity, absorbance.
The aim is not to prove that the plastic is inert; it never quite is. It is to show that whatever it can release remains known and limited. That is the subject of our article on extractables and leachables.
USP 661.1, 661.2: the material, then the system
In the United States, the former chapter 661 has been replaced by two chapters, official since 1 December 2025. 661.1 covers materials of construction: identity, biological reactivity, physicochemical properties, additives, extractable metals. 661.2 covers the complete packaging system, as it will be used with the medicine.
Packaging already in use has no blanket exemption: its files must be brought up to date. Chapter 671 completes the set with performance tests, such as water vapour transmission and light transmission; see our article on permeability.
What this asks of the packaging manufacturer
The laboratory is responsible for the file, but it cannot build it alone. It needs its supplier to know the exact material, its grade and its additives, and to be told of any change.
This is one of the reasons for the ISO 15378 standard, which applies good manufacturing practice to primary packaging materials: traceable material, a controlled process, changes notified.
The pharmacopoeia does not choose the bottle for the pharmacist. It sets the list of proofs, and it is the material, batch after batch, that has to supply them.
Glossary
- Pharmacopoeia
- An official collection of quality standards for medicines, their materials and their containers.
- Monograph
- A pharmacopoeia text describing the requirements for a substance or material.
- Additive
- A substance added to the polymer: antioxidant, stabiliser, colourant.
- Biological reactivity
- A material's ability to cause a reaction on contact with cells or tissue.