Coagulation laboratory tests
Low molecular weight heparin (LMWH)

Author: Jeremy Parsons, M.D. (see Authors page)

Revised: 16 May 2016, last major update November 2012

Copyright: (c) 2002-2016,, Inc.

PubMed Search: Low molecular weight heparin (LMWH)

Table of Contents
Definition / general
Cite this page: Low molecular weight heparin (LMWH). website. Accessed June 21st, 2018.
Definition / general
  • Recommended to monitor using chromogenic antifactor Xa assay on specimens obtained up to 4 hours after subcutaneous injection of LMWH (Chest 2001;119:64S)
  • Recommended to use different calibrations for LMWH and unfractionated heparin, and to establish calibration curves for each lot and type of LMWH
  • Don’t use PTT to monitor because LMWH doesn’t affect thrombin or factor IXa