Open AccessDigoxin–Trimethoprim Interaction
Author(s) -
PETERSEN PALLE,
KASTRUP JENS,
BARTRAM REINHOLD,
HANSEN JENS MØLHOLM
Publication year - 1985
Publication title -
acta medica scandinavica
Language(s) - English
Resource type - Journals
eISSN - 0954-6820
pISSN - 0001-6101
DOI - 10.1111/j.0954-6820.1985.tb02718.x
Subject(s) - digoxin , medicine , renal function , trimethoprim , clearance , pharmacokinetics , endocrinology , serum concentration , elimination rate constant , oral administration , pharmacology , urology , antibiotics , heart failure , chemistry , volume of distribution , biochemistry
Nine patients (median age 78 years, range 62–92) treated with a constant oral dosage of digoxin were evaluated for the effect of trimethoprim on serum digoxin values. Serum digoxin increased by 22% during trimethoprim treatment ( p <0.05). Subsequently, 6 healthy subjects (median age 29 years, range 24–31) were evaluated for the effect of trimethoprim on digoxin pharmacokinetics after an i.v. dose. Trimethoprim administration did not affect total body clearance of digoxin and the glomerular filtration rate. The renal clearance of digoxin decreased by 17% ( p <0.05) and the extrarenal clearance of digoxin increased by 14% (N.S.). Biological half‐life of digoxin and apparent volumes of central and peripheral compartments were unchanged during the study. It is suggested that the increase in serum digoxin in the elderly patients is due to decreased renal tubular secretion of digoxin and not to disturbance of the extrarenal clearance.