Sample Registration

Therapeutic drug monitoring

dr Konrad Kowalski
Chief Scientific Officer
Therapeutic drug monitoring is a process aimed at optimizing pharmacotherapy for an individual patient based on the measurement of drug concentration in the blood, pharmacokinetic principles, and pharmacodynamic criteria.
This allows for:
  • verification of previously used drug dosage regimen
  • correct dosage regimen to reduce drug toxicity
  • improving the effectiveness of the treatment and reducing its costs
  • safety of using high doses of potentially highly toxic drugs
Pharmacokinetics of a drug refers to the study of its absorption, distribution, metabolism, and excretion, as well as the influence of physiological, pathophysiological, and environmental factors and concomitantly used other drugs on the course of these processes. This information is necessary for proper interpretation of the results obtained, considering the patient's clinical state and the time of blood sampling for analysis.
Not all drugs require therapeutic drug monitoring. Drugs that are monitored include anticonvulsants, antiarrhythmics, cytotoxic drugs, antidepressants, immunosuppressants, which are characterized by:
  • potent action with a narrow therapeutic index, i.e., a small range between therapeutic and toxic concentrations
  • non-linear pharmacokinetics (lack of a proportional relationship between concentration and dose
  • large inter-individual variability in concentrations following a usual dose
  • the potential for numerous interactions with other drugs used concomitantly
TDM provides an alternative to empirical dosage selection based on trial and error, as well as a rational basis for individualising drug dosing and accelerating the achievement of the therapeutic goal.

Methods used in therapeutic drug monitoring:

Abbreviation Method
AED_SP Quantification of antiepileptic drugs in plasma/serum by LC-MS/MS technique