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close this bookThe Use of Essential Drugs: Eight report of the WHO Expert Committee (WHO - OMS, 1998, 84 p.)
View the document(introduction...)
View the documentWHO Expert Committee on the Use of Essential Drugs - Geneva, 1-5 December 1997
View the document1. Introduction
View the document2. Guidelines for establishing a national programme for essential drugs
View the document3. Criteria for the selection of essential drugs
View the document4. Guidelines for the selection of pharmaceutical dosage forms
Open this folder and view contents5. Quality assurance
Open this folder and view contents6. Reserve anti-infective agents and monitoring of resistance
View the document7. Applications of the essential drugs concept
Open this folder and view contents8. Essential drugs and primary health care
View the document9. Drug donations
View the document10. Post-registration drug studies
Open this folder and view contents11. Research and development
View the document12. Nomenclature
View the document13. Drug information and educational activities
View the document14. Selection and updating of lists of essential drugs
View the document15. Model List of Essential Drugs (tenth list)
View the document16. Considerations and changes made in revising the model list
View the document17. Glossary of terms used in the report
View the documentAcknowledgement
View the documentReferences
View the documentAnnex 1. Application form for inclusion in the Model List of Essential Drugs1
View the documentSelected WHO publications of related interest
View the documentBack Cover

17. Glossary of terms used in the report

In the course of its work, the Expert Committee used certain terms with the meanings given below:

Benefit/risk ratio

The ratio of benefit to risk in the use of a drug; a means of expressing a judgement concerning the role of the drug in the practice of medicine, based on efficacy and safety data along with consideration of misuse potential, severity and prognosis of the disease, etc. The concept may be applied to a single drug or in comparisons between two or more drugs used for the same condition.


The rate and extent of absorption of a drug from a dosage form as determined by its concentration/time curve in the systemic circulation or by its excretion in urine.


Faithful adherence by the patient to the prescriber’s instructions.

Dosage form

The form of the completed pharmaceutical product, e.g. tablet, capsule, elixir, suppository.


Any substance in a pharmaceutical product that is used to modify or explore physiological systems or pathological states for the benefit of the recipient.

Drug formulation

The composition of a dosage form, including the characteristics of its raw materials and the operations required to process it.

Drug utilization

The marketing, distribution, prescription and use of drugs in a society, with special emphasis on the resulting medical, social and economic consequences.


The ability of a drug to produce the purported effect as determined by scientific methods.


Any component of a finished dosage form other than the claimed therapeutic ingredient or ingredients.

Pharmaceutical product

Synonymous with dosage form.


The study of the rate of drug action, particularly with respect to:

- the variation of drug concentrations in tissues with time, and

- the absorption, distribution, metabolism and excretion of drugs and metabolites.