For many drugs commonly used in pediatrics, a suitable drug formulation or dosage strength is not commercially available. For that reason, children frequently receive medicines that are designed for adults, a practice called “unlicensed” or “off-label use.” The dose of commercially available products is adapted, mostly based on the child’s bodyweight, thereby neglecting differences in pharmacokinetic and pharmacodynamic parameters. Nowadays, serious attempts are being made to develop medicines, formulations, and dosage forms that are adapted to the specific needs of children. Several scientific guidelines have been released by the Food and Drug Administration (FDA) and the European Medicines Agency (EMA) concerning the development of medicines for children.