Therapeutic drug monitoring of plasma concentrations of antihypeensive drugs is not practiced because:
* TDM is done for drugs (with narrow therapeutic index) whose response cannot be monitored by simple laboratory parameters. * Antihypeensive effect can be easily measured, therefore TDM is not required.
Determination of plasma level of these drugs is quite tedious and long process
It is easier to measure the effect of these drugs
Antihypeensive effect do not increase linearly with the dose
All antihypeensive drugs are prodrugs
Pharmacodynamics