Drugs used to treat children are often not licensed for use in this age group. Examples of licensed medicines used outside the conditions of the licence (‘off label’ usage) include the oral administration of a vitamin K injection preparation, and cisapride, which is commonly prescribed for infants, but is not licensed for children under 2 years of age. The main reason many drugs are not licensed for use in children is that drug trials, and in particular pharmacokinetic studies, are difficult to undertake in the young child. This leads to a reluctance on the part of pharmaceutical companies to become involved in such trials. In Ireland, the Control of Clinical Trials and Drugs Act 19901 has led to problems in paediatric research. In the United Kingdom, clinical trials in children are conducted with the consent of a local or hospital ethics committee. Before 1987, this was also the case in …