This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Regamey, C. Articles by Kirby, W. M. M. Search for Related Content PubMed PubMed Citation Articles by Regamey, C. Articles by Kirby, W. M. M.

 Previous Article  |  Next Article 

Antimicrob Agents Chemother. 1972 April; 1(4): 329-332
Copyright © 1972 American Society for Microbiology. All Rights Reserved.

Inhibitory Effect of Heparin on Gentamicin Concentrations in Blood

¹ Department of Medicine, University of Washington School of Medicine, Seattle, Washington 98195

ABSTRACT

In monitoring gentamicin concentrations in the blood of patients with renal insufficiency, the assayed antibiotic concentration was found to be lower when the sample was drawn as heparinized plasma rather than as serum. This lowering of gentamicin concentrations by heparin was studied further by adding increasing doses of heparin and various amounts of gentamicin to human serum. With a range of 2 to 100 units of heparin per ml, gentamicin concentrations in the serum were lowered by 9 to 14%; with higher heparin concentrations, an even greater and increasing inhibition was noticed, reaching 56% for 1,000 units/ml. This inhibitory effect of heparin on gentamicin was reversible by dilution, indicating that it was not due to degradation or to formation of an inactive chemical complex. Underestimation by the laboratory of gentamicin concentrations in blood is likely to be greatest with capillary tubes, with which the concentration of heparin is especially high. With clinical heparinization, the amount of active heparin in the blood does not exceed 10 units/ml and is for the most part under 3 units/ml; thus, therapeutically significant inhibition of the antibiotic is unlikely in patients receiving anticoagulation.

This article has been cited by other articles:

• Droste, J. C., Jeraj, H. A., MacDonald, A., Farrington, K. (2003). Stability and in vitro efficacy of antibiotic-heparin lock solutions potentially useful for treatment of central venous catheter-related sepsis. J Antimicrob Chemother 51: 849-855 [Abstract] [Full Text]