Medicine Personalization
How genetics, lifestyle and biology are shaping the future of individualised treatment
Medicine personalisation is transforming how treatments are prescribed by moving away from a one-size-fits-all approach. By using an individual's genetic makeup, lifestyle, and environment, clinicians can select the right drug at the right dose for the right patient — improving outcomes and reducing harm. This approach is increasingly supported by pharmacogenetic testing and whole-genome analysis.
Why one-size-fits-all medicine isn't enough
Traditional drugs work well for approximately 60% of people — but 40% receive little or no benefit, or experience dangerous side effects. The reason lies in our genes: just 0.1% variation in DNA between individuals causes profound differences in how each person absorbs, breaks down, and responds to medicines. These differences mean that a dose that works perfectly for one person may be toxic or ineffective for another.
What is personalised medicine?
Personalised medicine — also called precision medicine — tailors treatment to your genes, body chemistry, lifestyle, and environment. The goal is the right drug, at the right dose, for the right patient, at the right time. It replaces guesswork and trial-and-error prescribing with a more precise, evidence-based approach built around the individual rather than the average patient.
The science behind it
Pharmacogenetics studies how individual genes affect drug response. Pharmacogenomics uses the entire genome to understand and improve medicines. Tiny genetic changes called SNPs (single nucleotide polymorphisms) affect enzymes — particularly the cytochrome P450 (CYP) family — that break down drugs in the liver. A 'fast metaboliser' may clear a drug too quickly for it to work; a 'slow metaboliser' may accumulate dangerous levels from a standard dose.
Real-world examples
Herceptin (trastuzumab) is only prescribed to breast cancer patients whose tumours overexpress the HER2 gene — without that genetic marker, the drug offers no benefit. Warfarin dosing is now guided by CYP2C9 and VKORC1 gene testing to prevent bleeding or clot complications. In leukaemia, a simple blood test for TPMT enzyme activity before prescribing 6-mercaptopurine can prevent potentially fatal toxicity — this is now standard practice.
The future of personalised prescribing
The field is advancing rapidly. Rapid point-of-care genetic tests before prescribing are already in use in some hospitals. Future clinical records will integrate full genomic profiles alongside traditional medical history. Research is even exploring 3D-printed pills with personalised doses and release profiles. The long-term goal is near-100% treatment effectiveness with minimal side effects for every patient — making medicine as individual as the people it treats.