Objective: To analyze the case reports concerning children (14 years or younger) in the Spanish Pharmacovigilance System over a 10-year period (1982-1991)., Findings: The study of 1419 reports of adverse drug reaction (9.8% of all those received) showed the most commonly involved organs and systems to be the skin, digestive tract, and nervous system (62.8%). The most commonly involved pharmacological groups were antibiotics, respiratory medications, and vaccines (69%). The absolute number of reports is higher in children between 1 and 4 years of age (37.9%). There were more reports among males than in females. Less than 5% of the reports notified directly life-threatening or fatal reactions., Conclusions: Adverse drug reaction are not common in pediatric patients, and most are mild. However, due to limitations of clinical trials in children, pharmacoepidemiological studies may be the only source of information on the benefit-risk profile of drugs received by these patients, and as such require special attention.