Developmental pharmacology: A moving target

Abstract The main characteristic of pediatric and neonatal pharmacotherapy still is the insufficient availability of drugs with confirmed efficacy and safety data in children. Children differ from adults in the physiological, psychological and developmental terms and this subsequently results in differences in anticipated drug potency, efficacy and toxicity. This paper is focused on the most prominent issues of the contemporary developmental pharmacology. Child's age and development can significantly affect drug pharmacokinetics (PK) processes. The dosage of drugs for children must be based on the physiological characteristics, as well as PK parameters of the drug obtained from the clinical trials with children. While knowledge about the impact of developmental changes on drug PK is increasing, information regarding pharmacodynamics (PD) is still more limited. The examples from clinical and animal data on ontogeny of receptors resulted in strong evidence for changes in drug response during development, in addition to but independent from PK alterations. In order to improve the use of medicines in children, it is essentially to know the complex processes of growth and development into the pediatric drug development programs. This is because absence of PK/PD data leads to increased risk of over- or under-dosing, adverse reactions or inefficiency.