Indications
Fondaparinux is an anticoagulant (blood-thinning) injection. It is used to prevent blood clots in the veins (deep vein thrombosis) and lungs (pulmonary embolism) after major hip or knee surgery, abdominal surgery, or in people who are bedridden with acute illness. It is also used to treat existing deep vein thrombosis and pulmonary embolism, and in some cases of acute coronary syndrome (unstable angina and certain heart attacks).
How It Works
Fondaparinux is a synthetic medicine that binds to antithrombin, a natural protein in the blood. This greatly increases antithrombin’s ability to block clotting factor Xa, an important step in clot formation. As a result, new clots are less likely to form and existing clots are less likely to grow.
Dosage and Administration
For prevention of clots, the usual adult dose is 2.5 mg injected under the skin once daily, as prescribed. After surgery, the first dose is usually given 6 hours after the operation, once bleeding is controlled. For treatment of existing clots, the dose depends on body weight and is set by the doctor. The injection is given by a doctor or nurse, or by the patient or a carer after proper training.
- Inject into the fatty tissue of the lower abdomen, alternating left and right sides.
- Do not rub the injection site, and do not expel the air bubble from the pre-filled syringe.
Interactions
The risk of bleeding increases when used with other anticoagulants or antiplatelet medicines, such as Warfarin, Heparin, Enoxaparin, Rivaroxaban, Apixaban, Aspirin, Clopidogrel, and with NSAIDs such as Ibuprofen or Diclofenac. Some antidepressants (SSRIs) can also add to bleeding risk. Tell your doctor about all medicines and supplements.
Contraindications
- Allergy to Fondaparinux.
- Active, clinically significant bleeding.
- Acute bacterial endocarditis (infection of the heart lining).
- Severe kidney impairment (creatinine clearance below 20 to 30 ml/min, depending on use).
Side Effects
Common side effects include bleeding (bruising, nosebleeds, bleeding gums, bleeding at the surgical or injection site), anaemia, and changes in liver tests. Rarely, low platelet count, rash or swelling may occur.
Get urgent medical help if you have heavy or uncontrolled bleeding, black or tarry stools, vomiting blood, blood in the urine, a sudden severe headache, weakness or numbness, or if after spinal or epidural anaesthesia you notice back pain, tingling, numbness or weakness in the legs, or loss of bladder or bowel control.
Pregnancy and Lactation
There is limited information on use in pregnancy; it should be used only if clearly needed and prescribed by a doctor. It is not recommended during breastfeeding unless the doctor advises it.
Precautions and Warnings
Use with care in people with bleeding disorders, recent stomach ulcer, recent brain, spine or eye surgery, uncontrolled high blood pressure, kidney impairment, low body weight (under 50 kg) and in older people. Spinal or epidural anaesthesia or puncture during treatment carries a risk of a blood clot around the spinal cord, so timing is planned carefully by the doctor. Blood counts and kidney function may be checked during treatment.
Overdose
Overdose can cause serious bleeding. There is no specific antidote. Seek emergency medical help; treatment is stopped and supportive measures are given in hospital.
Therapeutic Class
Anticoagulant, selective factor Xa inhibitor.
Storage
Store below 30°C in a dry place. Do not freeze. Keep out of the reach of children.
Prepared by the Oshud Alo team from standard drug references. For information only; always follow your doctor's advice.