enoxaparin

enoxaparin

(en ocks' a par in)

Lovenox

Pregnancy Category B

Drug classes

Low–molecular-weight heparin

Antithrombotic

Therapeutic actions

Low–molecular-weight heparin that inhibits thrombus and clot formation by blocking factor Xa, factor IIa, preventing the formation of clots.

Indications

·        Prevention of DVT, which may lead to pulmonary embolism following hip replacement, knee replacement surgery, abdominal surgery

·        Prevention of ischemic complications of unstable angina and non–Q-wave MI

·        Treatment of DVT, pulmonary embolus with warfarin

·        Prevention of DVT in medical patients who are at risk for thromboembolic complications due to severely restricted mobility during acute illnesses

Contraindications and cautions

·        Contraindicated with hypersensitivity to enoxaparin, heparin, pork products; severe thrombocytopenia; uncontrolled bleeding.

·        Use cautiously with pregnancy or lactation, history of GI bleed, spinal tap, spinal/epidural anesthesia

Available forms

Injection—30 mg/0.3 mL; 40 mg/0.4 mL; 60 mg/0.6 mL; 80 mg/0.8 mL; 100 mg/1 mL; 120 mg/0.8 mL; 150 mg/mL; 300 mg/3 mL

Dosages

ADULTS

·        DVT prophylaxis: 30 mg subcutaneously bid with initial dose soon as possible after surgery, not more than 24 hr after surgery. Continue throughout the postoperative period for 7–10 days; then 40 mg daily subcutaneously for up to 3 wk may be used.

·        Patients undergoing abdominal surgery: 40 mg/day subcutaneously begun within 2 hr preoperatively and continued for 7–10 days.

·        Outpatient DVT treatment: 1 mg/kg subcutaneously q 12 hr.

·        Inpatient DVT treatment: 1.5 mg/kg subcutaneously once daily.

·        Unstable angina and non–Q-wave MI: 1 mg/kg subcutaneously q 12 hr for 2–8 days.

·        Prevention of DVT in high-risk medical patients: 40 mg/day subcutaneously for 6–11 days, has been used up to 14 days.

PEDIATRIC PATIENTS

Safety and efficacy not established.

Pharmacokinetics

Route	Onset	Peak	Duration
SC	20–60 min	3–5 hr	12 hr

Metabolism: T_1/2: 4.5 hr

Distribution: May cross placenta; may enter breast milk

Excretion: Urine

Adverse effects

·        Hematologic: Hemorrhage; bruising; thrombocytopenia; elevated AST, ALT levels; hyperkalemia

·        Hypersensitivity: Chills, fever, urticaria, asthma

·        Other: Fever; pain; local irritation, hematoma, erythema at site of injection, epidural or spinal hematoma with spinal tap, spinal/epidural anesthesia

Interactions

Drug-drug

·        Increased bleeding tendencies with oral anticoagulants, salicylates, NSAIDs, penicillins, cephalosporins

·        Risk of severe bleeding if combined with heparin

Drug-lab test

·        Increased AST, ALT levels

Drug-alternative therapy

·        Increased risk of bleeding if combined with chamomile, garlic, ginger, ginkgo, and ginseng therapy, high-dose vitamin E

Nursing considerations

Assessment

·        History: Recent surgery or injury; sensitivity to heparin, pork products, enoxaparin; lactation; history of GI bleed; pregnancy

·        Physical: Peripheral perfusion, R, stool guaiac test, PTT or other tests of blood coagulation, platelet count, renal function tests

Interventions

·        Give drug as soon as possible after hip surgery, within 12 hr of knee surgery, and within 2 hr preoperatively for abdominal surgery.

·        Give deep subcutaneous injections; do not give enoxaparin by IM injection.

·        Administer by deep subcutaneous injection; patient should be lying down. Alternate between the left and right anterolateral and posterolateral abdominal wall. Introduce the whole length of the needle into a skin fold held between the thumb and forefinger; hold the skin fold throughout the injection.

·        Apply pressure to all injection sites after needle is withdrawn; inspect injection sites for signs of hematoma; do not massage injection sites.

·        Do not mix with other injections or infusions.

·        Store at room temperature; fluid should be clear, colorless to pale yellow.

·        Provide for safety measures (electric razor, soft toothbrush) to prevent injury to patient who is at risk for bleeding.

·        Check patient for signs of bleeding; monitor blood tests.

·        Alert all health care providers that patient is taking enoxaparin.

·        Discontinue and initiate appropriate therapy if thromboembolic episode occurs despite enoxaparin therapy.

·        WARNING: Have protamine sulfate (enoxaparin antidote) readily available in case of overdose.

·        Treat overdose as follows: Protamine sulfate (1% solution). Each mg of protamine neutralizes 1 mg enoxaparin. Give very slowly IV over 10 min.

Teaching points

·        Have periodic blood tests to monitor your response to this drug.

·        You and a significant other may need to learn to give the drug by subcutaneous injection and how to properly dispose of needles and syringes.

·        Avoid injury while you are taking this drug: Use an electric razor; avoid activities that might lead to injury.

·        Report nose bleed, bleeding of the gums, unusual bruising, black or tarry stools, cloudy or dark urine, abdominal or lower back pain, severe headache.

Adverse effects in Italic are most common; those in Bold are life-threatening.