Recent advancements in genomics and “omic” technologies have ushered in a transformative era referred to as personalized or precision medicine. This innovative approach considers the unique genetic profiles of individuals, along with a range of variability factors, to devise tailored disease treatments and prevention strategies that cater to the distinct needs of each patient. Although the terms personalized medicine and precision medicine are frequently utilized interchangeably, it is essential to delineate the subtle distinctions between them. Personalized medicine concentrates on bespoke treatments and prevention strategies that are meticulously tailored for each individual. Conversely, precision medicine utilizes advanced gene sequencing and comprehensive data analytics to formulate specific treatments and prevention strategies for defined groups of individuals based on genetic, environmental, and lifestyle factors rather than focusing exclusively on individual patients. Therefore, precision medicine constitutes an extension of traditional personalized care, improving the accuracy of diagnosis, prognosis, and therapy estimations for each patient through the application of sophisticated molecular diagnostics and advanced imaging techniques enabled by recent technological innovations. The shift from personalized to precision medicine has gained considerable traction, particularly in the wake of the 2015 US Precision Medicine Initiative, which has further stimulated advancements in this domain. This review will explore multiomics approaches that have facilitated the evaluation of personalized biomarkers associated with allergen immunotherapy, particularly in the treatment of allergic diseases. By leveraging these innovative methodologies, we aspire to cultivate more effective and individualized patient care, ultimately enhancing health outcomes for individuals with allergies.