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Updated: Jun 11, 2026
11:17
Multiplex Therapeutic Drug Monitoring by Isotope-dilution HPLC-MS/MS of Antibiotics in Critical Illnesses
Published on: August 30, 2018
[Dosing of digitoxin in clinical practice]
Arne Hønnås1, Arne Reimers, Olav Spigset
1Avdeling for klinisk farmakologi, St. Olavs hospital, 7006 Trondheim, Norway.
Summary
Norwegian digitoxin guidelines changed in 2007, lowering target serum concentrations. Despite this, digitoxin levels remain high, especially in older patients, necessitating dose adjustments.
Area of Science:
- Pharmacology
- Clinical Chemistry
Context:
- New Norwegian guidelines in 2007 recommended lower digitoxin serum concentrations (8-15 nmol/l).
- Previous recommendations were approximately 50% higher than the 2007 guidelines.
Purpose:
- To analyze trends in digitoxin dosing and serum concentrations from 2000-2008.
- To evaluate the impact of updated guidelines on digitoxin levels.
Summary:
- Median digitoxin serum concentrations decreased from ~25 nmol/l to 19 nmol/l after 2007.
- Mean daily digitoxin dose decreased from 66 µg to 56 µg.
- Elderly patients (>85 years) exhibited nearly double the digitoxin concentrations compared to younger patients (<55 years).
Impact:
- Digitoxin serum concentrations have decreased post-2007 but frequently exceed the new reference range.
- Lowering digitoxin doses is crucial to achieve target concentrations, particularly for elderly individuals.
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