Children and adults respond to drugs differently. There are Important differences In the absorption, distribution, metabolism, and excretion of medications during infancy and childhood. Children's body systems are less developed; their gastrointestinal transit time varies; and their body composition changes with development. This article will explore pediatric pharmacokinetics, the effect the body has on a drug, and the Implications for practice. The controversial off-label use of medications must be considered when prescribing medications because specific dosage guidelines for the pediatric population still are not available for the majority of marketed drugs. Prescription writing must be appropriate, legible, and meticulous. Family education about medications and administration techniques is an essential part of the clinician's role. The limited scope of current research in pharmacokinetics and the effects on the developing child creates the need for more studies on drug therapy and the pediatric client. Furthermore, clinicians need to expand research on the effects of parental education on accurate medication administration and drug therapy compliance.