Image for arixtra Fondaparinux is a blood thinner used to prevent blood clots from forming.

When a blood clot forms in a vein in the legs, it is called deep vein thrombosis (DVT). DVT can block blood flow through the vein. Symptoms include pain, swelling, warmth, and a change in skin color of the affected leg. Sometimes, symptoms do not occur unless a clot breaks loose and travels through the bloodstream to the lungs. This is called pulmonary embolism and can be fatal. People who undergo certain surgeries are at high risk of developing DVT.

When Is Fondaparinux Prescribed?

Your doctor may prescribe fondaparinux after certain types of surgery, including hip or knee replacement, hip fracture repair, or abdominal surgery. This medication may be prescribed to people who are very ill and have risk factors for blood clots. Fondaparinux may also be used along with other blood thinners to treat DVT and pulmonary embolism.

How Is Fondaparinux Given?

This medication is given as an injection under the skin.

What Are the Side Effects?

Fondaparinux can cause many side effects. Some of these include:

Who Should Not Take This Medication?

Like all blood-thinning drugs, fondaparinux can cause excessive, dangerous bleeding. The risk of bleeding is greater for certain groups of people. You will not be able to take fondaparinux if you have any of these conditions:

  • Severe kidney disease
  • Weigh less than 110 pounds
  • Active major bleeding, bacterial endocarditis (an infection that affects the heart), and thrombocytopenia (low blood platelet count)

What Are the Precautions With This Medication?

If you are prescribed fondaparinux:

  • Be sure to carefully follow your doctor's instructions, especially if you are aged 75 or older. You may experience more side effects.
  • Tell your healthcare providers, including dentists, that you are taking fondaparinux.
  • Because you are taking fondaparinux, you will bleed more easily. Ask your doctor about steps that you can take to prevent injuries.
  • Tell your doctor if you are taking any other medications, including over-the-counter drugs, herbs, and supplements.
  • If you are pregnant or breastfeeding, talk to your doctor before taking this medication.

In rare cases, you may be more likely to have severe bleeding after certain procedures, including: