Core pharmacology

Class Group

Anticoagulants

Legacy Cicm Level

Level 1

Introduction

Enoxaparin is a LMWH prepared from
unfractionated heparin by controlled
enzymatic or chemical depolymerisation
Consists of smaller fragments of
Heparin. MW: Average of 5000 Daltons

Indications Uses

1. the prevention of venous thromboembolic disease
2. the treatment of acute coronary syndromes.

Presentation

Usually s/c, but can be given i.v.
20mg or 40mg BD s/c as prophylaxis, 1mg/kg BD s/c as therapeutic dose

Monitor:
Anti-Xa level

Mechanism of action

Activates antithrombin but due to shorter length preferentially inhibits factor Xa

Adverse Effects Toxicity

Bleeding
Needs adjustment in renal failure
Less HITS and osteoporosis

Absorption

up to 90% via SC (greater than heparin)

Protein binding

less prot bind than heparin

Volume of distribution

Vd ~ 0.1L/kg

Metabolism

Hepatic depolymerisation and desulfation to less active fragments

Excretion

urine as 40% of dose and 10% active fragments, dose adjustment in renal failure

Half-life

2-4 times longer half-life than heparin
dose independent half time

Special Points

Reversal:
Protamine by slow infusion
Less e¬ffective than heparin due to the preferential Xa action (1mg/1mg
LMWH), but max effect is < 60%