Monday February 5, 2007
If there is bleeding with LMWH

If protamine is given within 4 hours of the enoxaparin (Low Molecular Weight Heparins - LMWH), then a neutralizing dose is: 1 mg of protamine per 1 mg of enoxaparin. The IV protamine should be administered slowly atleast over 10 minutes as rapid infusion may cause anaphylactoid type reaction. May repeat half of earlier dose of protamine after 6 hours with postulation that half life of enoxaparin is longer than protamine.

LMWH, dalteparin (Fragmin) appears to be more responsive to protamine reversal.

2 bonus pearls

1. Protamine does not help in reversing bleeding from Fondaparinux (Arixtra). Only supportive treatment should be given with mean half-life of fondaparinux of 17-21 hours in mind.

2. Fresh frozen plasma is ineffective in reversal of LMWH to achieve hemostasis and should not be use in these situations.


References: Click to get article/abstract

1. Accidental overdosage following administration of Lovenox - rxlist.com
2. Incomplete Reversal of Enoxaparin Toxicity by Protamine: Implications of Renal Insufficiency, Obesity, and Low Molecular Weight Heparin Sulfate Content - Obesity Surgery, Volume 14, Number 5, 1 May 2004, pp. 695-698(4)