Enoxaparin Use in Adult Patients

Objectives

The purpose of this guideline is to provide assistance in the dosing and management of the low molecular weight heparin enoxaparin in adult inpatients eighteen years of age or older (>18 years) regardless of location. See the dosing guidelines for pediatric patients for patients < 18 years of age.

University of Michigan Health System

Anticoagulation Program

Guideline for Dosing and Management of Enoxaparin in Adult Inpatients

Dosing Guidelines (see table 1)

Route of administration
- Enoxaparin is administered subcutaneously for all indications outlined in this guideline.
- The preferred site for administration is the abdomen. Alternate sites include the upper arm or the thigh.
Treatment indications
- The recommended dosing regimen for enoxaparin is 1.5mg/kg every 24 hours, unless a contraindication to this dosing strategy exists.
- The dose in patients with a creatinine clearance < 30 mL/min (via Cockcroft-Gault) is 1 mg/kg every 24 hours, regardless of indication or comorbidities.
- In certain circumstances an alternate dosing strategy is recommended (see Table 1).
- Actual body weight should be used for dose determination.
Prophylaxis indications (Prevention of Venous Thromboembolism)
- Non-Pregnant Patients
  - Dose is determined based upon renal function and actual body weight
- Pregnant Patients
  - Dose is determined based upon ante-partum gestation or time frame post-partum

Table 1: Dosing Guidelines

(Note: All doses are to be administered subcutaneously)

TREATMENT
Indication	Dose*#
Usual dose	1.5 mg/kg every 24 hours
Patients with CrCl < 30 mL/min, regardless of indication or comorbidities	1 mg/kg every 24 hours^
Dose alteration if CrCl >30 mL/min and:	1 mg/kg every 12 hours
Weight > 150 kg
Mechanical heart valve
Active cancer
Left ventricular assist device (LVAD)
Hemodynamically unstable PE
Acute Coronary Syndrome (ACS)
Pregnancy
Atrial fibrillation ablation with CrCl ≥30 mL/min	0.5 mg/kg every 12 hours

PROPHYLAXIS/PREVENTION of VTE
Nonpregnant patients:
CrCl > 30 mL/min	40 mg every 24 hours (for ABW < 150 kg) 30 mg every 12 hours (for ABW > 150 kg)
CrCl <30 mL/min	30 mg every 24 hours (regardless of ABW)
Trauma patients:
CrCl > 30 mL/min	30 mg every 12 hours (regardless of ABW)
CrCl <30 mL/min	30 mg every 24 hours (regardless of ABW)
Pregnant patients:
Less than 20 weeks gestation	40 mg every 24 hours
20 weeks gestation until 1 week post-partum	40 mg every 12 hours
Post-partum weeks 2-6	40 mg every 24 hours

*Actual body weight should be used for dose determination

#Doses will be rounded to the nearest whole syringe size as outlined in Enoxaparin (Lovenox) Dose Rounding Table.

^Creatinine clearance as calculated by Cockcroft-Gault

Monitoring Guidelines

Treatment Indications

Routine Monitoring
- Baseline and ongoing monitoring of renal function and hematologic parameters should be performed in accordance with UMHHC Policy 07-01-051 (UMHHC Inpatient Anticoagulation Monitoring Table)
Anti-Factor Xa Activity Monitoring
- Routine Anti-Factor Xa activity level monitoring is not recommended.
- Anti-Factor Xa activity levels may be considered in the following patients receiving enoxaparin:
  1. Obese patients (greater than 200 kg)
  2. Renal insufficiency (CrCl less than 30 ml/min)
  3. Pregnant patients
  4. Patients on long-term therapy
- Sample Collection and Timing
  1. Sample should be drawn after 3 doses of enoxaparin, at steady state
  2. Peak level is recommended and should be drawn 4-6 hours post-dose
  3. Trough level is preferred in renal impairment (CrCl less than 30ml/min) on enoxaparin treatment dosing (1mg/kg every 24 hours)
- Goal Anti-Factor Xa activity levels

(Note: these levels should be viewed as general guidelines as extensive correlation data lacks with efficacy and safety outcomes)

Regimen	Target Anti-Factor Xa Activity Level (units/mL)
Enoxaparin 1 mg/kg every 12 hours	0.5-1
Enoxaparin 1.5 mg/kg every 24 hours	1-2
Enoxaparin 1 mg/kg every 24 hours	Trough (preferred): less than 0.4

Dosing Nomogram for Peak Anti-Factor Xa Activity for Enoxaparin 1 mg/kg every 12 hours (round to nearest available dose)

Anti-Factor Xa Activity Level (units/mL)	Dose Change
Less than 0.35	Increase by 25%
0.35-0.49	Increase by 10%
0.5-1	NO DOSE CHANGE
1.1-1.5	Decrease by 20%
1.6-2	Decrease by 30%
Greater than 2	Hold 1 dose, then decrease by 40%
Repeat anti-Factor Xa activity level with 3rd dose after adjustment

Dosing Nomogram for Peak Anti-Factor Xa Activity for Enoxaparin 1.5 mg/kg every 24 hours (round to nearest available dose):

Anti-Factor Xa Activity Level (units/mL)	Dose Change
Less than 0.5	Increase by 25%
0.5-0.9	Increase by 10%
1-2	NO DOSE CHANGE
2.1-2.5	Decrease by 20%
Greater than 2.5	Hold 1 dose, then decrease by 30%
Repeat anti-Factor Xa activity level with 3rd dose after adjustment

If dose adjustments are made based upon nomograms and repeat Anti-Factor Xa Activity is desired, sample should be drawn after 3 doses as outlined above.

Prophylaxis Indications

Routine Monitoring
- Baseline and ongoing monitoring of renal function and hematologic parameters should be performed in accordance with UMHHC Policy 07-01-051< UMHHC Inpatient Anticoagulation Monitoring Table>
Anti-Factor Xa Activity Monitoring
1. Not recommended

Conversion To And From Other Oral Or Parenteral Anticoagulant Agents For Treatment Indications

Converting from warfarin to enoxaparin
- Start enoxaparin when INR is equal to or below the lower end of the therapeutic range for the patient’s indication.
Converting from enoxaparin to warfarin
- Start warfarin therapy while continuing enoxaparin therapy. Once INR reaches the therapeutic range for the patient, discontinue enoxaparin.
Converting from another anticoagulant other than warfarin to enoxaparin

Alternate Anticoagulant

Time after last dose of alternate anticoagulant

before start of enoxaparin

Unfractionated heparin or parenteral direct thrombin inhibitor IV continuous infusion

Start enoxaparin immediately upon discontinuation of continuous infusion

Subcutaneous fondaparinux; oral dabigatran or rivaroxaban

Start enoxaparin 0 – 2 hours before the next dose of alternate anticoagulant was to be administered

Converting from enoxaparin to another anticoagulant other than warfarin

Alternate Anticoagulant	Time after last dose of enoxaparin before start of alternate anticoagulant
Unfractionated heparin IV continuous infusion	Start infusion at the time the next dose of enoxaparin would have been given and consider use of a bolus dose
Parenteral direct thrombin inhibitor IV continuous infusion	Start infusion at the time the next dose of enoxaparin would have been given
Subcutaneous fondaparinux; oral dabigatran or rivaroxaban	Give first dose of alternate anticoagulant at the time the next dose of enoxaparin would have been given

Special Thanks

Attribution

If reusing this content please use the following information to provide credit to the content authors:

Title: Enoxaparin Use in Adult Patients
Author: Michigan Medicine
Source: https://ecosystem.tactuum.com/
License: “CC BY-NC 4.0”

Enoxaparin Use in Adult Patients, Michigan Medicine, Dept of Surgery, “CC BY-NC 4.0”

References

American College Chest Physicians. Chest 2008 Guidelines for Antithrombotic and Thrombolytic Therapy. CHEST. 2008;133 (6):67S-70S.
Laposata et al. College of American Pathologists Conference XXXI on Laboratory Monitoring of Anticoagulant Therapy: The Clinical Use and Laboratory Monitoring of Low-Molecular-Weight Heparin, Danaproid, Hirudin and Related Compounds, and Argatroban. Arch Pathol Lab Med. 1998;122:799-807.
Duhl AJ et al. Antithrombotic Therapy and Pregnancy: Consensus Report and Recommendations for Prevention and Treatment of Venous Thromboembolism and Adverse Pregnancy Outcomes. Am J Obstet Gynecol. 2007;197:457.e1-e21.

Last reviewed: 09 June 2021