CHARACTERISTICS OF TOPICS IN PHARMACOVIGILANCE IN THE NETHERLANDS

A retrospective analysis was made of the nature and composition of 107 consecutive topics presented in publications by or in collaboration w ith the national pharmacovigilance centre in The Netherlands, containi ng data obtained through 'spontaneous reporting'. These tropics were p ublished in various national and international professional journals o r special bulletins or as 'dear doctor letters'. The topics constitute d a wide variety of events and disorders. There was, however, a predom inance of concrete, characteristic and often serious diseases, notably specific hypersensitivity reactions (43%, e.g. anaphylaxis, blood dys crasias and liver injury), toxic manifestations or syndromes (30%, esp ecially involving the nervous system), and drug interactions (13%). Mo st topics presented predominantly qualitative information. 62% of topi cs concerned type B, 33% type A and 3% type C adverse drug effects. Th e topics often referred to small numbers of case reports: 10 or less i n 70% of the 107 topics. 46% of the topics concerned new information. There was some predominance of established (56%) over new drugs. Five pharmacotherapeutic groups accounted for 74% of topics. Of the 72 appr oved drugs or drug groups, 12 (17%) have been removed from the market. These findings increase our understanding of the functioning of pharm acovigilance and may enable further improvement of the methods and str ategies involved.