Pharmacotherapy gains importance in newborns due to the differences in body physiology. Newborns need special drug treatments due to their anatomical, physiological, and biochemical differences that change the pharmacokinetics and pharmacodynamics of various drugs. Factors such as gastric pH and emptying time, intestinal transit time, immaturity of secretion, total body water, immaturity of the neurological and the urinary systems may result in age-related changes in pharmacokinetics and pharmacodynamics. Due to the immaturity of the body systems of the newborns, the absorption, distribution, metabolism, and excretion of the drugs from the body are different from that in adults. Knowing the pharmacokinetics of the drugs in medicaments and their appropriate treatment is of great importance in the prevention of drug errors. From these perspectives, neonatology nurses have crucial roles to play in providing patient safety in their care. The aim of this review is to develop a guide regarding the essential principles of pharmacokinetics in newborns and safe drug administrations. In this review, the newborn pharmacokinetics and nursing approaches are examined under three subtitles: (1) pharmacological definitions-principles, (2) pharmacokinetics in newborns, and (3) responsibilities of the nurse. It is expected that this study will guide neonatal nurses in practice and shed light for further research and new studies on pharmacotherapy and safe drug administrations.