Quality Assurance of Pharmaceuticals - A Compendium of Guidelines and Related Materials - Volume 1
(1997; 248 pages) [French] View the PDF document
Table of Contents
Open this folder and view contentsIntroduction
Open this folder and view contents1. National drug regulation
Close this folder2. Product assessment and registration
View the documentGuidelines for the assessment of herbal medicines1,2
Close this folderStability of drug dosage forms1
View the document1. Introduction
View the document2. General considerations
Open this folder and view contents3. Responsibility of parties involved in the assurance of drug stability
View the document4. Use of terms
View the document5. Less stable drug substances
View the documentReferences
Open this folder and view contentsGuidelines for stability testing of pharmaceutical products containing well established drug substances in conventional dosage forms1
Open this folder and view contentsMultisource (generic) pharmaceutical products: guidelines on registration requirements to establish interchangeability1
Open this folder and view contents3. Distribution
Open this folder and view contents4. The international pharmacopoeia and related activities
Open this folder and view contents5. Basic tests
Open this folder and view contents6. Laboratory services
Open this folder and view contents7. International trade in pharmaceuticals
Open this folder and view contents8. Counterfeit products
Open this folder and view contents9. Training
View the documentSelected WHO publications of related interest
View the documentBack cover

4. Use of terms

The following working definitions or explanations are offered for a number of the terms used in this text.

Stability: The ability of a drug to retain its properties within specified limits throughout its shelf-life. The following aspects of stability are to be considered: chemical, physical, microbiological and biopharmaceutical.

Expiry (expiration) date: The expiry date placed on the container of a drug product designates the date up to and including which the product is expected to remain within specification if stored correctly. It is established for every batch by adding the shelf-life period to the manufacturing date.

Shelf-life (expiration dating period or validity period): The period of time during which a drug product is expected, if stored correctly, to remain within specification as determined by stability studies on a number of batches of the product. The shelf-life is used to establish the expiry date of each batch.

Provisional (tentative) shelf-life: The provisional shelf-life is determined by projecting results from accelerated stability studies.

Date of manufacture: A date fixed for the individual batch, indicating the completion date of the manufacture. It is normally expressed by a month and a year. The date of the release analysis may be taken as a date of manufacture, provided that the period between the beginning of production and the release of the product is not longer than one-twentieth of the shelf-life.

Normal storage conditions: Storage in dry, well-ventilated premises at temperatures of 15-25 °C or, depending on climatic conditions, up to 30 °C. Extraneous odours, other indications of contamination, and intense light have to be excluded.

Defined storage instructions: Drug products that must be stored under defined conditions require appropriate storage instructions. Unless otherwise specifically stated, e.g. continuous maintenance of cold storage, deviation may be tolerated only during short-term interruptions, for example during local transportation.

The following instructions are recommended:

On the label




“Do not store over

30 °C”

from +2 °C to +30 °C

“Do not store over

25 °C”

from +2 °C to +25 °C

“Do not store over

15 °C”

from +2 °C to +15 °C

“Do not store over

8 °C”

from +2 °C to +8 °C

“Do not store below

8 °C”

from +8 °C to +25 °C


“Protect from moisture”

no more than 60% relative humidity in normal storage conditions; to be provided to the patient in a moisture-resistant container


“Protect from light”

to be provided to the patient in a light-resistant container

Stability tests: The purpose of stability tests is to obtain information in order to define the shelf-life of the pharmaceutical product in its original container and to specify storage conditions.

Accelerated (stress) stability studies: Studies designed to increase the rate of chemical or physical degradation of a drug by using exaggerated storage conditions with the purpose of monitoring degradation reactions and predicting the shelf-life under normal storage conditions. The design of accelerated studies may include elevated temperature (e.g. 37-40 °C and up to 50-55 °C), high humidity and light.

Only a provisional shelf-life may be established on the basis of these studies. Therefore, accelerated studies should always be supplemented by real-time studies under expected storage conditions,

Utilization period: A period of time during which a reconstituted preparation or the preparation in an opened multidose container can be used.

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