The basic (simplified) tests described in this manual represent one of the many elements of quality assurance in the pharmaceutical supply system. They have been devised with the following objectives:

(a) to provide a simple and readily applicable method for verifying the identity of a drug substance, using a limited range of easily available reagents, when the labelling and physical attributes give rise to doubt;

(b) to provide a practicable means of confirming the identity of a drug, when a fully equipped laboratory is not available;

(c) to indicate if gross degradation has occurred in certain substances that are known to decompose readily under adverse conditions.

Basic tests are not, in any circumstances, intended to replace the requirements of The International Pharmacopoeia^aor other pharmacopoeial monographs. These give an assurance of quality whereas basic tests merely confirm identity.

^aThe International Pharmacopoeia, third edition. Geneva, World Health Organization. Volume 1: General methods of analysis, 1979. Volume 2: Quality specifications, 1981. Volume 3: Quality specifications, 1988.

In several European countries, simple tests have already been endorsed by the national pharmaceutical associations for use at peripheral levels of distribution (wholesale premises, pharmacies) to verify the identity of pharmaceutical substances whenever the possibility of confusion arises and sometimes to exclude gross degradation or adulteration.

In 1986, the manual Basic tests for pharmaceutical substances^bwas published by the World Health Organization. It is now complemented by this volume, which contains tests for 150 pharmaceutical dosage forms, most of which are included in the WHO Model List of Essential Drugs.^c Each of the tests described has been verified in at least four laboratories in different countries. Analogous tests for further dosage forms are in preparation and will be published separately.

^bBasic tests for pharmaceutical substances. Geneva, World Health Organization, 1986.

^c WHO Technical Report Series, No. 796, 1990.

Degradation during storage and transportation is of particular importance in tropical countries. Indeed, an expiry date determined for a temperate climate may be inappropriate in a tropical region even when high standards of packaging are met. For this reason, particular importance is accorded to visual inspection of dosage forms, since this frequently provides a first vital indication of degradation. This also applies in cases where there are reasons to suspect quality defects due to poor manufacture, tampering or counterfeiting.

Basic tests need not be carried out by fully qualified pharmacists or chemists, but they should be performed by persons with some understanding of analytical chemistry such as that acquired in courses for pharmaceutical assistants.

Several tests are described for most preparations. Not all of these need to be applied to any one sample. If, however, there is any reason to suspect that the product is mislabelled or substandard, all tests described should be performed. By their nature, simplified tests cannot be totally reliable. An adverse result, even in one test, should be taken as a warning of potential unsuitability of a drug. In these circumstances, a final conclusion should not be drawn until a full analytical examination has been carried out in a properly equipped quality control laboratory.

The proposed tests are supplemented by advice on visual inspection and a short description of the minimum facilities and equipment needed to carry out the work. The reagents needed for testing dosage forms are listed at the end of this publication.

Comments on the tests described are invited and should be addressed to: Pharmaceuticals, World Health Organization, 1211 Geneva 27, Switzerland.