Therapeutic Drug Monitoring (TDM)

Therapeutic Drug Monitoring (TDM) is a clinical pharmacokinetic practice in which drug concentrations are measured in a patient's blood to guide individualized dosing. It applies principally to drugs with narrow therapeutic windows—where the margin between efficacy and toxicity is small—such as aminoglycosides, vancomycin, cyclosporine, and antiepileptics. Developed as a formal discipline in the 1980s, TDM integrates measured concentrations with pharmacokinetic modeling to calculate patient-specific dose regimens.