For decades, prescribing medicine has followed a "one-size-fits-all" playbook: a standard drug, a standard dose, and a hopeful wait to see how the patient responds. The pharmacogenomic testing service is quietly dismantling that model. By reading the genetic variants that govern how an individual absorbs, metabolizes, and reacts to a drug, this branch of precision diagnostics is helping clinicians answer a question that used to be guesswork: will this medicine actually work for this patient, at this dose, without causing harm? From oncology wards choosing the right targeted therapy to psychiatrists shortening the frustrating trial-and-error of antidepressant selection...