Pharmacogenomics is a rapidly evolving field that examines the influence of genetic variations on drug response, efficacy, metabolism, and toxicity. The integration of genomic information into clinical decision-making has transformed traditional healthcare approaches by enabling personalized drug therapy tailored to individual genetic profiles. Variations in genes encoding drug-metabolizing enzymes, transporters, receptors, and signaling molecules significantly affect therapeutic outcomes and adverse drug reactions. Pharmacogenomic testing facilitates the selection of appropriate medications, optimization of dosage regimens, and reduction of treatment-related complications. The application of pharmacogenomics has gained considerable attention in oncology, cardiology, psychiatry, infectious diseases, and pain management. Advances in next-generation sequencing, bioinformatics, artificial intelligence, and precision medicine initiatives have accelerated the implementation of pharmacogenomics in healthcare systems worldwide, remarkable progress, several challenges including high testing costs, limited clinical awareness, ethical concerns, and regulatory complexities continue to hinder widespread adoption. This review discusses the fundamental principles of pharmacogenomics, its clinical applications, technological advancements, implementation challenges, and future prospects in precision healthcare management. The growing integration of genomic data into routine clinical practice is expected to enhance treatment effectiveness, improve patient safety, and contribute significantly to the development of personalized medicine.