Pharmacovigilance

PHARMACOVIGILANCE

Pharmacovigilance has been defined by the WHO as the ‘science and activities relating to the detection, assessment, understanding and prevention of adverse effects or any other drug related problems.’ The information generated by pharmacovigilance is useful in educating doctors about ADRs and in the official regulation of drug use. It has an important role in rational use of medicines, as it provides the basis for assessing safety of medicines.

The activities involved in pharmacovigilance are:

    a.   Postmarketing surveillance and other methods of ADR monitoring such as voluntary reporting by doctors (e.g. yellow card system of UK), prescription event monitoring, computerized medical record linkage and other cohort/case control studies as well as anecdotal case reports by doctors.

Voluntary reporting depends on the initiative and willingness of the health professionals. It is minimal in India, while even in the developed countries only ~10% ADRs are reported voluntarily. Generally, immediately occurring reactions and those that are dramatic are reported. Though even rare reactions can be detected by this method, it does not provide incidence of the reaction.

          b. Dissemination of ADR data through ‘drug alerts’, ‘medical letters,’ advisories sent to doctors by pharmaceuticals and regulatory agencies (such as FDA in USA, committee on safety of medicines in UK).

c. Changes in the labelling of medicines indicating restrictions in use or              statuary warnings, precautions, or even withdrawal of the drug.

Pharmacovigilance centres have been set up in most countries. The Uppsala Monitoring Centre (Sweden) is the international collaborating centre. In India, the national coordinating centre is located in the All India Institute of Medical Sciences. Regional centres are expected to collect, communicate and disseminate ADR data by linking with medical institutions and practitioners. The pharmacovigilance centres are also expected to provide expertise for assessing causality and severity of ADRs by using standard algorithms and rating scales.