Pharmacogenomics studies how genetics affects how drugs affect the human body. The terms genomics and pharmacology are the sources of the field's name, which represents the intersection of genetics and medicine. The discovery of the laws of heredity in 1866 marked the beginning of the area of pharmacogenetics (PGx). The FDA has established PGx testing recommendations, so whenever these 250+ drugs are being reviewed, testing should be considered. Physicians in the fields of pain management, mental health, and cardiovascular health are among those who provide PGx recommendations. Antidepressant medications offer several therapeutic options that are similar, which makes them a prime candidate for the use of PGx. It makes sense that pharmaceutical companies are hesitant to use pharmacogenomics in clinical investigations given its relative youth. Clinical trials and pharmacogenomic testing together have many advantages. Finding populations with risk factors unrelated to the medication itself may also be facilitated by pharmacogenetics. Oral anticoagulants and chemotherapy treatment regimens are now recommended based on a patient's pharmacogenetic condition. When it comes to patient dosing, pharmacogenetic techniques are gradually replacing the traditional method of depending solely on trial and error. The present therapeutic application of pharmacogenetics can also be applied to drug research and development.