Pharmacovigilance represents all methods of detection, assessment, inf
ormation and prevention of adverse drug reactions (ADRs). It mainly in
volves the post-marketing phase because of the low probability of dete
cting all possible adverse effects of a drug during pre-marketing deve
lopment. The most widely used method for pharmacovigilance is spontane
ous reporting which is an excellent signal generator but precludes sat
isfactory calculation of incidence rates. The French Pharmacovigilance
System has been set up in 1973; reporting of ADRs has been made manda
tory in 1984 for prescribers. This system consists in a network of 30
regional centres under supervision of a coordinating committee at the
French Drug Agency. The number of ADR cases received, assessed and rec
orded by the regional centres is around 10,000 per year; a similar num
ber of cases are reported to the Drug Agency by the pharmaceutical ind
ustry. Moreover, Regional Centres work as Drug Information Centres ans
wering more than 23,000 inquiries per year.