[Therapeutic drug monitoring of digitoxin--results of 3 years' experience].
Between 1986 and 1988 within our therapeutic drug monitoring plasma concentrations were estimated in 1,442 plasma samples by radioimmunoassay. Plasma levels between 0 and 84.2 ng.ml-1 with a mean of 20.8 ng.ml-1 were measured. If the maintenance dose was reduced from 0.1 to 0.07 mg the frequency distribution of the plasma samples was shifted to the left, and the mean value decreased by 5.8 ng.ml-1 (23.5 vs. 17.7 ng.ml-1). The physician's assumptions underdosage?, optimum dosage schedule? or overdosage? were confirmed by the laboratory results in 22.3, 63.6, or 23.0% of the requests, respectively. In 61.2% of all plasma samples were digitoxin concentrations in the range between 10 and 30 ng.ml-1, i.e. in the optimum therapeutic range. Main reasons for the divergent results are non-compliance of the patients and inter-individual differences in the pharmacokinetics of digitoxin. Furthermore, incomplete filling of the forms by the physicians aggravates the assessment of the results. Therefore, a permanent dialogue between clinician and clinical pharmacologist is necessary for an improvement of digitalis therapy.
Haustein
K O
KO
Institut für Klinische Pharmakologie, Medizinischen Akademie Erfurt.
Winkler
U
U
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001145:Arrhythmias, Cardiac / Q000139:chemically induced; D002648:Child; D002675:Child, Preschool; D004074:Digitoxin / Q000008:administration & dosage / Q000009:adverse effects / Q000493:pharmacokinetics*; D004305:Dose-Response Relationship, Drug; D006333:Heart Failure / Q000097:blood* / Q000188:drug therapy; D006801:Humans; D007223:Infant; D008875:Middle Aged; D011863:Radioimmunoassay
D004074:Digitoxin
Therapeutic-Drug-Monitoring für Digitoxin-Ergebnisse einer 3jährigen Erfahrung.