Pharmacogenetics is the scientific field that studies the interaction between an individual’s genetic makeup and medications. Genetic variations in the structures responsible for metabolizing and eliminating drugs from the body can affect the efficacy and side effects of medications. Therefore, pharmacogenetic testing performed before treatment can guide dose adjustments and help predict adverse events such as hypersensitivity, lack of therapeutic response, or significant side effects.

Uses of Pharmacogenetic Tests

Pharmacogenetic tests are used for:

• Distinguishing patients who respond well to a drug from those who do not.

• Determining the optimal drug dose planned for therapy.

• Taking precautions for patients in whom drug concentrations could reach toxic levels in plasma or tissues.

• Minimizing the need for medications that may fall outside standard drug-gene interactions.

• Implementing necessary measures for patients with a personal or family history of unexpected drug responses.

• Providing lifelong genetic information to guide safe and effective use of multiple medications, including potential drug-drug interactions.

In recent years, new drugs have been developed for cancer treatment, particularly for targeted therapies. Pharmacogenetic tests play a key role in identifying which patients are most likely to benefit from these medications. Genetic testing has become standard practice, especially prior to treatment with new drugs for breast, colorectal, lung, gastrointestinal cancers, and malignant melanoma.