VALUE, LIMITATIONS AND CLINICAL IMPACT OF THERAPEUTIC DRUG-MONITORINGIN ADULTS

In 3 groups of unselected hospitalised patients treated with digoxin ( n = 300), gentamicin (n = 140) or theophylline (n = 120), physicians' special request forms for routinely performed therapeutic drug monitor ing (TDM) of steady-state plasma levels (plus peak levels in the case of gentamicin) were evaluated in order to test whether TDM services ha d any impact on physician prescribing and dosing. All the data necessa ry for the correct interpretation of results were available only in th e request forms of 65.7%, 70% and 70% of patients on digoxin, gentamic in and theophylline, respectively. 75% of digitalised patients, 96% of patients on theophylline, and all patients on gentamicin were in stea dy-state when blood sampling was carried out. In 16% of patients on ge ntamicin, peak samples were taken more than 30 minutes after the end o f infusion. TDM service revealed proper modification of the dose in on ly 12 of 49 patients on digoxin, 20 of 65 on gentamicin, and 15 of 78 on theophylline therapy. It can be concluded that TDM is frequently in correctly applied by physicians and permanent efforts are needed for i ts proper use during daily routine work.