Poor product quality, adverse drug reactions (ADRs), and medication errors greatly influence health care systems by negatively affecting patient care and increasing costs. Most of the statistics documenting the issues and highlighting the importance of pharmacovigilance come from developed countries, therefore low- and middle income countries likely have greater problems because of the poorer state of their health system infrastructure, the unreliable supply and quality of medicines, the lack of adequately trained essential health care staff, and their limited access to communication and information technology. Three areas of pharmacovigilance include -
- Product quality
- Adverse drug reactions
- Medication errors
Product quality problem reporting systems are covered in Chapter 19 on quality assurance. This chapter focuses on the importance of ADRs and medication errors and actions to take to minimize their impact. An ADR is a harmful response caused by the medicine after the patient has received it in the recommended manner; whereas, adverse drug events (ADEs) result from either the medicine itself or the medicine’s inappropriate use or medication error.
Health professionals may still think of pharmacovigilance strictly in terms of identifying and reporting previously unknown and serious ADRs related to new products; however, pharmacovigilance activities are related to every sector of the pharmaceutical management framework: selection, procurement, distribution, use, management support, and the overarching policy and legal framework. Likewise, pharmacovigilance activities are carried out at the facility, national, and international levels and require collaboration among a wide range of partners with differing responsibilities. National governments are responsible for ensuring that medicines sold in their countries are of good quality, safe, and effective. An important component of a country’s ability to monitor pharmaceutical safety is a national pharmacovigilance system that is supported by the drug regulatory authority. However, some countries have not included pharmacovigilance as part of their legal framework. Public health programs, such as those for treating HIV/AIDS and malaria, may have separate pharmacovigilance systems, while hospitals usually have the capacity to design and implement facility-based medication safety activities.
The major components of a pharmacovigilance system are data collection, which can be passive, active, or mandatory, and data analysis and reporting. When ADEs occur, they must be analyzed and reported and their significance must be communicated effectively to an audience that has the knowledge to interpret the information, including the national pharmacovigilance center, if one exists, and the World Health Organization (WHO) Programme for International Drug Monitoring. Based on the results of the analysis, actions should be carried out to reduce adverse drug events and thereby improve patient care. To encourage continued participation in the process, interventions should be shared with the data reporters. Follow-up data collection and analysis can then measure the effectiveness of the interventions. The use of medicines involves a trade-off between benefits and the potential for harm. Pharmacovigilance can help minimize harm by ensuring that medicines of good quality are used rationally.