Pharmacogenomics is the application of genetic and other omics data to specific medication selection and application for avoiding adverse drug reactions (ADR) and increasing drug potency. Pharmacists are playing an increasingly important role in optimizing medicine usage based on genetic testing results. Effect elucidation, genotype-guided medication and modification, medication asset, adverse reaction monitoring, and patient education are all tasks performed by pharmacists. Microbial invasion leads to infectious diseases, which have afflicted mankind from the early era, and is still impacting the health and one of the major causes of morbidity as well as mortality in the society. The response to therapy and the prognosis of an illness are also influenced by an individual’s genetic makeup. The data retrieved by genome sequencing of pathogen and humans is one further step forward in examining host-parasite interactions. Consideration of microbial pathogenicity factors, host genetic makeup, and the genetic mechanism involved in disease pathogenesis has paved the way for novel molecular approaches for medications, disease markers, and vaccinations to be discovered. The regulatory approval of amplification tests that are comparable or patronizing to existing gold standard procedures is now assisting the advancement of molecular diagnostics for infectious diseases. Progress in genetics and computation is altering the scale at which biological systems are depicted, and researchers may now expect a precision-focused variety in how they prepare for and respond to infectious diseases. This review will look at the origins and evolution of pharmacogenomics, as well as some of the controversies surrounding its therapeutic applications.