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Low Molecular Weight Heparin/Prescription

LOVENOX (PRESERVATIVE FREE)

LOVENOX (PRESERVATIVE FREE)

Clinical safety rating

caution

Comprehensive clinical and safety monograph for LOVENOX (PRESERVATIVE FREE) (LOVENOX (PRESERVATIVE FREE)).


Mechanism of Action

Low molecular weight heparin (LMWH) that potentiates antithrombin III, accelerating inactivation of factor Xa and thrombin.

What the body does with it

MetabolismMetabolized primarily by desulfation and depolymerization in the liver via heparinases; renally eliminated as unchanged drug and metabolites.
ExcretionRenal: 40-60% as unchanged drug and low molecular weight fragments via glomerular filtration; biliary/fecal: negligible.
Half-lifeTerminal half-life: 3-5 hours after subcutaneous injection; prolonged in renal impairment (up to 8-10 hours with CrCl <30 mL/min).
Protein bindingApproximately 90% bound to antithrombin III (minor binding to other plasma proteins).
Volume of Distribution4-7 L (0.06-0.1 L/kg) – predominantly confined to intravascular space.
BioavailabilitySubcutaneous: ~90-100% (almost complete absorption).
Onset of ActionSubcutaneous: 30-60 minutes (anti-Factor Xa activity detectable within 30 min).
Duration of ActionSubcutaneous: Anti-Factor Xa activity persists for approximately 12 hours; clinical anticoagulation effect lasts 12-24 hours.
Molecular Weight4000-6000 Da (average 4500 Da)

Classification & Brands

Dosing & administration

1 mg/kg subcutaneously every 12 hours or 1.5 mg/kg subcutaneously once daily.

Dosage formINJECTABLE
Renal impairmentFor CrCl <30 mL/min: reduce dose to 1 mg/kg subcutaneously once daily. For CrCl 30-50 mL/min: no dose adjustment required, but monitor carefully.
Liver impairmentNo specific dose adjustment recommended for hepatic impairment; caution in severe hepatic impairment due to increased bleeding risk.
Pediatric useNeonates: 1.5 mg/kg subcutaneously every 12 hours. Infants and children: 1 mg/kg subcutaneously every 12 hours.
Geriatric useNo specific dose adjustment, but increased risk of bleeding; monitor renal function and adjust dose if CrCl <30 mL/min.

Use during pregnancy

1st trimesterAvoid use unless clearly needed; increased risk of spontaneous abortion and congenital anomalies in animal studies, but human data limited.
2nd trimesterUse with caution if anticoagulation necessary; no known teratogenic risk, but monitor for bleeding complications.
3rd trimesterIncreased risk of maternal hemorrhage, placental abruption, and fetal bleeding; use only if benefit outweighs risk, and consider reversal agent availability.

Clinical note

Comprehensive clinical and safety monograph for LOVENOX (PRESERVATIVE FREE) (LOVENOX (PRESERVATIVE FREE)).

Placental transferDoes not cross the placenta significantly due to high molecular weight and charge; maternal anti-Xa activity does not correlate with fetal levels.
BreastfeedingExcreted into breast milk in low amounts; unlikely to cause adverse effects in infants due to poor oral bioavailability, but caution in premature infants or with renal impairment. Monitor for bruising or bleeding.
Lactation RatingL2 - Probably Compatible
Teratogenic RiskLow risk of teratogenicity; enoxaparin does not cross the placenta and is not associated with fetal malformations. In the first trimester, risk of teratogenicity is minimal but consider anticoagulation alternatives if VTE prophylaxis needed; second and third trimesters: no known teratogenic risk, but increased risk of maternal bleeding and placental abruption; perinatal: risk of neonatal bleeding if administered near delivery.
Fetal MonitoringMonitor maternal anti-Xa levels (peak 3-4 hours post-dose) if dose adjustment needed; assess platelet count every 2-3 days for heparin-induced thrombocytopenia; monitor for signs of bleeding, placental abruption, and fetal distress via nonstress test or biophysical profile in high-risk pregnancies.
Fertility EffectsNo known adverse effects on fertility; may be used in assisted reproductive technology for thrombophilia without impairing implantation or ovarian function.

Warnings & precautions

■ FDA Black Box Warning

Spinal/epidural hematomas, including subsequent paralysis, may occur in patients anticoagulated with LMWH or heparinoids who receive neuraxial anesthesia or undergo spinal puncture. Risk increased by use of indwelling epidural catheters, concomitant use of drugs affecting hemostasis, history of traumatic or repeated epidural/spinal punctures, or history of spinal deformity or surgery.

Side Effect Profile

Serious Effects

Absolute Contraindications

Hypersensitivity to enoxaparin or heparinActive major bleedingHistory of heparin-induced thrombocytopenia (HIT)Epidural or spinal anesthesia within 12 hours of administration (for once-daily regimen) or 24 hours (for twice-daily regimen) due to risk of spinal hematomaSevere uncontrolled hypertension

Clinical Precautions

PrecautionsRisk of bleeding; thrombocytopenia, including heparin-induced thrombocytopenia (HIT); use in renal impairment (reduce dose if CrCl <30 mL/min); elderly patients (increased bleeding risk); pregnancy (category B); use with caution in patients with history of heparin-induced thrombocytopenia; monitor for signs of bleeding.
Food/DietaryNo known direct food interactions. However, foods high in vitamin K (e.g., green leafy vegetables, broccoli, Brussels sprouts) may theoretically affect coagulation but are not a concern with LMWH. Avoid or limit alcohol consumption due to increased bleeding risk.

Clinical Tips & Counseling

Clinical PearlsLovenox (enoxaparin) is a low molecular weight heparin (LMWH) that does not require routine monitoring of anti-Xa levels except in special populations (e.g., renal impairment, obesity, pregnancy). Use with caution in patients with severe renal impairment (CrCl <30 mL/min) as enoxaparin accumulates; consider dose reduction or alternative agent. Protamine sulfate can partially reverse anticoagulation (1 mg protamine per 1 mg enoxaparin). Risk of spinal/epidural hematoma with neuraxial anesthesia or spinal puncture; remove catheter at least 12 hours after last prophylactic dose and 24 hours after last treatment dose. Contraindicated in active major bleeding, history of heparin-induced thrombocytopenia (HIT), or hypersensitivity to heparin products. Calculate dose based on actual body weight, not ideal body weight, for treatment indications.
Patient AdviceDo not stop taking or change the dose without consulting your healthcare provider. · Report any signs of bleeding (unusual bruising, prolonged bleeding, blood in urine/stool, coughing up blood, bleeding gums) or injection site reactions (pain, redness, swelling). · Avoid aspirin, NSAIDs (ibuprofen, naproxen), or other blood thinners unless prescribed by your doctor. · Inform your doctor if you are pregnant, plan to become pregnant, or are breastfeeding. · If you have an epidural or spinal tap, inform your doctor that you are taking enoxaparin. · Store at room temperature; do not freeze. Use prefilled syringes only once and dispose of properly. · If you miss a dose, take it as soon as possible unless it is almost time for the next dose; do not double the dose.

LOVENOX (PRESERVATIVE FREE) Interactions

Loading safety data…

This overview is compiled from peer-reviewed clinical sources and FDA labeling. It's here to support — not replace — clinical judgment. Always verify dosing against your institution's current protocols before prescribing.

On this page

Mechanism of ActionDosing & administrationUse during pregnancyWarnings & precautionsDrug interactions

Compare with

EMBOLEXEnoxaparinENOXAPARIN SODIUMENOXAPARIN SODIUM (PRESERVATIVE FREE)INNOHEP

External sources

DailyMed (NIH) PubMed OpenFDA