tinzaparin sodium

tinzaparin sodium Warning - High-alert drug!

Innohep

Pharmacologic class: Low-molecular-weight heparin

Therapeutic class: Anticoagulant

Pregnancy risk category B

FDA Boxed Warning

• During epidural or spinal anesthesia or puncture, patients receiving drug or scheduled to receive it for thromboprophylaxis are at risk for epidural or spinal hematoma, which can lead to long-term or permanent paralysis. Risk increases with use of indwelling epidural catheter for analgesia administration and with concurrent use of drugs affecting hemostasis (such as nonsteroidal anti-inflammatory drugs [NSAIDs], platelet inhibitors, and other anticoagulants). Risk also rises with traumatic or repeated epidural or spinal puncture. Before neuraxial intervention, physician should weigh drug's potential benefit against risk.
• Monitor patient frequently for signs and symptoms of neurologic impairment. If these occur, provide urgent interventions.

Action

Enhances inhibition of factor Xa and thrombi by binding to and accelerating activity of antithrombin III; has only slight effect on thrombin and clotting time

Availability

Injection: 20,000 anti-Xa international units/ml in 2-ml vials

⊘Indications and dosages

➣ Deep-vein thrombosis

Adults: 175 anti-Xa international units/kg subcutaneously daily for at least 6 days and until patient is adequately anticoagulated with warfarin for 2 consecutive days

Off-label uses

• Pulmonary embolism

Contraindications

• Hypersensitivity to drug, heparin, sulfites, benzyl alcohol, or pork products
• Active major bleeding
• History of heparin-induced thrombocytopenia

Precautions

Use cautiously in:
• renal impairment; bacterial endocarditis; uncontrolled hypertension; congenital or acquired bleeding disorders; hepatic failure and GI ulcers; recent brain, spinal, or ophthalmic surgery; diabetic retinopathy
• pregnant or breastfeeding patients
• elderly patients.

Administration

☞ Be aware that tinzaparin sodium is a high-alert drug.
• Give by deep subcutaneous injection into abdominal wall while patient is sitting or lying down.
• Don't rub injection site after removing needle.
• Observe injection site closely for hematoma.
• Rotate injection sites among four quadrants of abdominal wall.
☞ Don't give I.V. or I.M.
• Know that warfarin therapy usually starts within 1 to 3 days after tinzaparin therapy begins.

Route	Onset	Peak	Duration
Subcut.	2-3 hr	4-5 hr	18-24 hr

Adverse reactions

CNS: dizziness, insomnia, confusion, headache, cerebral or intracranial bleeding

CV: hypotension, hypertension, angina pectoris, chest pain, tachycardia, dependent edema, thromboembolism, arrhythmias, myocardial infarction (MI)

EENT: ocular hemorrhage, epistaxis

GI: nausea, vomiting, constipation, flatulence, dyspepsia, melena, GI hemorrhage, retroperitoneal or intra-abdominal bleeding

GU: urinary tract infection, hematuria, urinary retention, dysuria, vaginal hemorrhage

Hematologic: anemia, thrombocytopenia, granulocytopenia, agranulocytosis, pancytopenia, hemorrhage

Musculoskeletal: back pain, intra-articular hemorrhage

Respiratory: dyspnea, pneumonia, respiratory disorder, pulmonary embolism

Skin: pruritus, rash, bullous eruption, cellulitis, purpura, skin necrosis

Other: injection site hematoma and reactions, pain, fever, impaired healing, infection, hypersensitivity reaction, congenital anomaly, fetal distress, fetal death

Interactions

Drug-drug. Oral anticoagulants, platelet inhibitors (such as dextran, dipyridamole, NSAIDs, salicylate, sulfinpyrazone), thrombolytics: increased risk of bleeding

Vitamin A: increased anticoagulant effect

Drug-diagnostic tests. Alanine aminotransferase, aspartate aminotransferase: reversible elevations

Granulocytes, hemoglobin, platelets, red blood cells, white blood cells: decreased values

Drug-herbs. Alfalfa, anise, arnica, astragalus, bilberry, black currant seed oil, bladderwrack, bogbean, boldo (with fenugreek), borage oil, buchu, capsacin, cat's claw, celery, chaparral, chincona bark, clove oil, dandelion, dong quai, evening primrose oil, fenugreek, feverfew, garlic, ginger, ginkgo, guggul, papaya extract, red clover, rhubarb, safflower oil, skullcap, tan-shen: increased anticoagulant effect

Patient monitoring

• Monitor vital signs and ECG closely.
☞ Assess neurologic status. Stay alert for indications of intracranial or intracerebral bleeding.
• Evaluate closely for signs and symptoms of bleeding in all body systems.
☞ Monitor respiratory status carefully to detect pneumonia, pulmonary embolism, and other serious adverse reactions.
• Monitor cardiovascular status closely. Watch for signs and symptoms of thrombophlebitis and edema.
• Monitor CBC, platelet count, and coagulation studies. Assess stools for occult blood.

Patient teaching

☞ Tell patient to immediately report unusual bleeding or bruising. Inform him that drug can cause serious adverse reactions, especially bleeding. Instruct him to report new symptoms right away.
• Advise patient that aspirin products, NSAIDs, and many herbs increase the bleeding risk. Urge him to consult prescriber before using these products.
• Instruct patient to avoid activities that can cause injury. Tell him to use soft toothbrush and electric razor to avoid gum and skin injury.
• Tell patient he'll undergo regular blood tests during therapy.
• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs, tests, and herbs mentioned above.