Information about adverse drug reactions reported in children: a qualitative review of empirical studies

center dot Adverse drug reactions (ADRs) in children are common, and although some are serious, studies on this topic are scarce. center dot A review of studies published before 2000 showed that the overall incidence of ADRs in hospitalized children was 9.53% (95% CI 6.81, 12.26) and in outpatients 1.46% (95% CI 0.7, 3.03). WHAT THIS STUDY ADDS center dot Information about the occurrence and seriousness of reported ADRs, suspected medications, age and gender of children and type of reporter is only sparsely available in the literature. center dot Substantial amounts of information about ADRs occurring in children have been reported to national ADR databases and during chart review of hospitalized children in recent years. center dot The ADRs most commonly reported in children were of the types: (i) skin and subcutaneous disorders (range 15-65%); (ii) general disorders and administration site conditions (range 5-70%); (iii) gastrointestinal disorders (range 5-60%); and (iv) nervous system and psychiatric disorders (range 5-45%), mainly reported for the therapeutic groups: vaccines, antibiotics and psychotropic medicines. center dot The majority of reported ADRs concerned paediatric populations from North America and Europe. AIM To review the literature on adverse drug reactions (ADRs) in children with respect to occurrence, seriousness, type, therapeutic group, age and gender of the child and category of reporter. METHODS Medline and Embase databases were searched from origin and updated until February 2010. We included empirically based articles on ADRs in populations aged 0 to 17 years. Studies monitoring ADRs in patients with particular conditions or drug exposure were excluded. We extracted information about types and seriousness of ADRs, therapeutic groups, age and gender of the child and category of reporter. ADR occurrence was calculated as incidence rate and prevalence. RESULTS We included 33 studies monitoring ADRs in general paediatric populations. The highest numbers of ADRs were reported in national ADR databases where data were collected over a longer period than in studies monitoring inpatients and outpatients. However, prevalence and incidence were much lower in the national databases. Types of reported ADRs, seriousness of ADRs and types of medicines differed substantially between studies due to differences in time periods and patient populations. Information about ADRs was mainly provided by health care professionals, although parents also contributed reports. CONCLUSIONS We found a higher incidence rate of ADRs in hospitalized children and outpatients than in national databases. There seems to be considerable potential for increasing the knowledge of ADRs by advocating the submission of reports to the spontaneous reporting systems. Our study underscores that ADRs in children constitute a significant public health problem.