In 1962, in the wake of the thalidomide disaster, World Health Assembly requested WHO to establish an international system of monitoring adverse reactions to drugs using information derived from national centres. Before an effective international system could become operative, a common reporting form had to be developed, agreed guidelines for entering information had to be formulated, common terminologies and classifications had to be prepared and compatible systems for transmitting, storing, retrieving and disseminating data had to be created. Upon the successful completion of these tasks the operational activities subserving the international data base were relocated 1978 to a WHO collaborating centre situated in Upsala, Sweden.
ADRM in Bangladesh
In regard to safety and efficacy of drugs particularly those concern ADR's in Bangladesh left unanswered mainly due to lack of a systematic mechanism of monitoring.
Under the guidance of WHO, a cell has been established in Directorate of Drug Administration in 1996. Initially the cell circulated posters, bearing awareness slogans of drug use throughout the country, organized awareness meeting among the chemists of different area and also published awareness instructions in the daily newspapers and broadcasted these awareness slogans in Radio Bangladesh. The cell is trying to introduce a systematic mechanism for ADR monitoring program in Bangladesh for collection, analysis & compilation of ADRs which will be spontaneously reported by the medical & pharmaceutical professional from all health services outlets of the country.
The Ministry of Health & Family Welfare formed 10 (Ten) Members ADR Advisory Committee (ADRAC) on 6 July 1997 to evaluate, analyze & make recommendations for solving problems of medicinal hazards due to ADRs.
From the year 2000, Directorate of Drug Administration organized ADR monitoring workshops/ meetings in five Medical Colleges & Hospitals of the country and distributed printed ADR reporting forms for spontaneous report.
Side Effect
A side effect is 'any unintended effect of a pharmaceutical product occurring at doses normally used in man, which is related to the pharmaclological properties of the drug'. Essential elements in this definition are the pharmacological nature of the effect, that the phenomenon is unitended and that there is no overt overdose.
Adverse Reaction
An adverse reaction is 'a response to a medicine which is noxious and unintended and which occurs at doses normally used in man,. In this description it is of importance that it concerns the response of a patient, in which individual factors may play an important role, and that the phenomenon is noxious (an unexpected therapeutic response, for example, may be a side effect but not an adverse reaction.
Serious adverse events can be defined as those that:
a. are life-theratening or fatal
b. cause or prolong hospital admission
c. cause persistent incapacity or disability; or
d. concern misuse or dependence.
Type A effects ('drug actions') are those which are due to (exaggerated) pharmacological effects. Type A effects are tend to be fairly common, dose related (i.e. more frequent or severe with higher doses) and may often be avoided by using doses which are appropriate to the individual patient. Such effects can usually be reproduced and studied experimentally and are often already identified before marketing.
Type B effects (patient reactions) characteristically occur in only a minority of patients and display little or no dose relationship. They are generally rare and unpredictable and may be serous and are notoriously difficult to study. Type B effects are either immunological or non-immunological and occur only in patients, wich often unknown-predisposing conditions. Immunological reactions may range from rashes, anaphylaxix, vasculitis, inflammatory organ injury, to highly specific autoimmune syndromes. Aslo non-immunological Type B effects occur in a minority of predisposed intolerant patients, e.g. because of an inborn error of metabolism or acquired deficiency in a certain enzyme, resulting in an abnormal metabolic pathway or accumulation of a toxic metabolite. Examples are chloramphenicol aplastic anaemia and isoniazid hepatitis.
Type C effects refer to situation where the use of a drug, often for unknown reasons, increases the frequency of a spontaneous disease. Type C effects may be both serious and common (and include malignant tumours) and may have pronounced effects on public health. Type C effects may be coincidental and often concern long term effects there is often no suggestive time relationship and the connection may be very difficult to prove.