Pharmacovigilance

Pharmacovigilance, also known as drug safety, is the pharmacological science relating to the collection, detection, assessment, monitoring, and prevention of adverse effects with pharmaceutical products.

What is Pharmacovigilance?

Pharmacovigilance is defined as the science and activities concerned with the detection, assessment, understanding, and prevention of adverse reactions to medicines (i.e. adverse drug reactions or ADRs). The ultimate goal of this activity is to improve the safe and rational use of medicines, thereby improving patient care and public health.

Purpose of Pharmacovigilance

• Pharmacovigilance is the science and activities relating to the detection, assessment, understanding, and prevention of adverse effects or any other possible drug-related problems.
• Recently, its concerns have been widened to include:

1. herbals
2. traditional and complementary medicines
3. blood products
4. biologicals
5. medical devices
6. vaccines.

• Many other issues are also of relevance to the science:

1. substandard medicines
2. medication errors
3. lack of efficacy reports
4. use of medicines for indications that are not approved and for which there is an inadequate scientific basis
5. case reports of acute and chronic poisoning
6. assessment of drug-related mortality
7. abuse and misuse of medicines
8. adverse interactions of medicines with chemicals, other medicines, and food.

The specific Aim of Pharmacovigilance

• improves patient care and safety in relation to the use of medicines and all medical and paramedical interventions.
• improve public health and safety in relation to the use of medicines.
• contribute to the assessment of benefits, harm, effectiveness, and risk of medicines, encouraging their safe, rational, and more effective (including cost-effective) use.
• promote understanding, education, and clinical training in pharmacovigilance and its effective communication to the public.

Understanding of Pharmacovigilance

• Pharmacovigilance is the practice of monitoring the effects of medical drugs after they have been licensed for use. One important goal of this activity is to detect, collate, assess and monitor previously unreported adverse reactions, with the aim of preventing adverse effects and reducing the considerable economic and clinical costs associated with adverse reactions.
• Its main purpose is to reduce the risk of drug-related harm to the patient. It has an important role in the rational use of medicines as it provides the basis for assessing the safety of medicines.

Activities involved in Pharmacovigilance are:

• Post-marketing surveillance and other methods of ADR monitoring such as voluntary reporting by doctors, 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. 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 the incidence of the reaction.
• Dissemination of ADR data through ‘drug alerts’, ‘medical letters,’ advisories sent to doctors by pharmaceuticals and regulatory agencies (such as the FDA, committee on safety of medicines).
• Changes in the labeling of medicines indicate restrictions in use or statuary warnings, precautions, or even withdrawal of the drug, by the regulatory decision-making authority.

Importance of Pharmacovigilance

1. There are differences among countries (and even regions within countries) in the occurrence of ADRs and other drug-related problems.
2. This may be due to differences in diseases and prescribing practices, genetics, diet, traditions of the people, drug manufacturing processes used which influence pharmaceutical quality and composition, drug distribution and use including indications, dose, and availability.
3. The use of traditional and complementary drugs (e.g. herbal remedies) may also pose specific toxicological problems when used alone or in combination with other drugs.
4. Therefore, Pharmacovigilance is needed for detecting ADRs and specifically to combat counterfeit and substandard quality products. ADR monitoring ensures that patients obtain safe and efficacious products.

Pharmacovigilance – Why?

• At the time of approval, clinical trial data are available on limited numbers of patients treated for relatively short periods
• Once a product is marketed, large numbers of patients may be exposed, including:

1. Patients with co-morbid illnesses
2. Patients using concomitant medications
3. Patients with chronic exposure