Pharmacovigilance has the aim to provide updated information about drug safety and define a risk/benefit ratio for the population exposed to a drug. It operates through a surveillance activity of adverse drug reactions (ADRs) and through realization of a communication network to improve knowledge and information about ADRs among health care professionals.
Children represent a specific target population with unique pharmacokinetic and pharmacodynamic characteristics because of peculiarities in absorptive surfaces, body composition and enzymatic activities [1]. Few therapeutic indications are unique for children who require a relatively limited number of drugs. For these reasons, there is little incentive for pharmaceutical companies in performing studies in paediatric population; practical difficulties and ethical issues represent additional obstacles [2].  Pharmacokinetic, pharmacodynamic and safety data about paediatric drugs are lacking, exposing children to higher risk of experiencing ADRs.
A lot of drugs prescribed to hospitalized children are frequently used in an unlicensed and/or in an off-label way, since specific data about paediatric indications are lacking [3]. These prescription practices expose children to higher risk for development of ADRs. Hospitals pediatricians should try to pay more attention in administering such therapies to neonates, infants and children.
Another frequent prescription practice, especially in neonatal or paediatric intensive care units, is polypharmacotherapy, which increases the risk of developing ADRs. Hospitals pediatricians have the role of taking the best therapeutic decisions and contemporary of detecting any possible drug-related issues even in the case of polypharmacotherapy.
When an ADR is detected, it should be reported to the hospital’s pharmacology service that is responsible for reporting it to the competent health authorities. It has been estimated that reported ADR incidence in hospitalized children ranges from 4.3% to 16.7% [4]. Pediatricians in children’s hospitals represent the first step of the pharmacovigilance network. 
In more recent years, it has been largely discussed about the necessity of improving pharmacovigilance networks in general, and in paediatric population in particular. In Italy, ADRs reporting rate by pediatricians is far from being optimal. Pharmacovigilance activity in paediatric hospital settings needs to be improved; in the time period between 2001 and 2006 only very few ADRs reports came in fact from major children’s hospitals in South Italy [5]. 
In conclusion, there is a urgent need for the realization of a necessary passage from a “passive” pharmacovigilance, based exclusively on spontaneous reports of ADRs, to an “active” one, to be realized through a better organization of both human and infrastructural resources,  through creation of diseases or treatment registries and databases [6], and through performance of epidemiological post-marketing studies. In this new panorama, hospitals pediatricians should play a primary role in obtaining more data about effectiveness and safety of paediatric drugs in order to guarantee higher standards in the quality of care of paediatric patients.

 
REFERENCES:
[1] Kearns GL, Abdel-Rahman SM, Alander SW, et al. Developmental pharmacology – Drug disposition, action, and therapy in infants and children. N Engl J Med 2003;349:1157-67
[2] Burns JP. Research in children. Crit Care Med 2003;31:S131–S136
[3] World Health Organization. Promoting safety of medicines for children. 2007
[4] Impacciatore P, Choonara I, Clarkson A et al. Incidence of adverse drug reactions in paediatric in/out-patients: a systematic review and meta-analysis of prospective studies. J Clin Pharmacol 2001;52:77-83
[5] Reazioni avverse ai farmaci nei bambini: i dati della Rete Nazionale di Farmacovigilanza. BIF 2006;5:210-14
[6] EMEA. Guideline on conduct of pharmacovigilance for medicines used by paediatric population. 2007