Medical product vigilance refers to science and activities aimed at the prevention, detection, assessment and understanding of adverse effects – such as adverse events following immunization (AEFI) in the case of vaccines – or any other medical product–related problems. Vigilance is one of the key regulatory functions that assure the efficacy and safety of medical products on the market.

Pharmacovigilance enhances patient care and safety by monitoring the use of medicines and other health technologies, such as medical devices and procedures. It supports public health programmes by providing reliable, balanced information for the effective assessment of medical product benefit–risk profiles and encouraging their safe, rational and more effective and cost-effective use.

Vigilance is multidisciplinary, requiring expertise in areas such as molecular mechanisms of adverse drug reactions, clinical medicine, pharmacoepidemiology, information technology, pharmaceutical manufacturing, legal frameworks, public health and local cultural practices where medical products are used.