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Fondaparinux Injection

pronounced as (fon'' da par' in ux )


If you have an epidural or spinal anesthesia or a spinal puncture while using a 'blood thinner' such as fondaparinux injection, you are at risk for having a blood clot form in or around your spine that could cause you to become paralyzed. Tell your doctor if you have or have ever had spinal surgery, problems with pain medication given through the spine, a spinal deformity, or if you have bleeding problems. Tell your doctor and pharmacist if you are taking other anticoagulants ('blood thinners') such as warfarin (Coumadin), anagrelide (Agrylin), aspirin or nonsteroidal anti-inflammatory drugs (ibuprofen, naproxen), cilostazol (Pletal), clopidogrel (Plavix), dipyridamole (Persantine), eptifibatide (Integrilin), prasugrel (Effient), ticlopidine, and tirofiban (Aggrastat). If you experience any of the following symptoms, call your doctor immediately: muscle weakness, numbness or tingling (especially in your legs), or inability to move your legs.

Keep all appointments with your doctor and the laboratory. Your doctor may order certain tests to check your body's response to fondaparinux injection.

Talk to your doctor about the risk of using fondaparinux injection.

Why is this medication prescribed?

Fondaparinux injection is used to prevent deep vein thrombosis (DVT; a blood clot, usually in the leg), which can lead to pulmonary embolism (PE; a blood clot in the lung), in people who are having hip surgery, hip or knee replacement, or abdominal surgery. It is also used in along with warfarin (Coumadin, Jantoven) to treat DVT or PE. Fondaparinux injection is in a class of medications called factor Xa inhibitors. It works by decreasing the clotting ability of the blood.

How should this medicine be used?

Fondaparinux injection comes as a solution (liquid) to be injected subcutaneously (just under the skin) in the lower stomach area. It is usually given one time a day for 5 to 9 days or sometimes for up to about 1 month. You will probably begin using fondaparinux injection while you are in the hospital at least 6 to 8 hours after your surgery. Use fondaparinux injection at around the same time every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Use fondaparinux injection exactly as directed. Do not inject more or less of it or inject it more often than prescribed by your doctor.

If you will continue to use fondaparinux after your hospital stay, you can inject fondaparinux yourself or have a friend or relative perform the injections. Ask your doctor or pharmacist to show you or the person who will be injecting the medication how to inject it. Before you use fondaparinux injection yourself the first time, read the Patient Information that comes with it. This information includes directions for how to use and inject fondaparinux prefilled safety syringes. Be sure to ask your pharmacist or doctor if you have any questions about how to inject this medication.

Each syringe has enough medication in it for one shot. Do not use the syringe and needle more than one time. Your doctor, pharmacist, or healthcare provider will tell you how to dispose of used needles and syringes safely.

Do not mix fondaparinux injection with other medications or solutions.

Other uses for this medicine

Fondaparinux injection is also sometimes used to help prevent blood clots in people who have had a heart attack. Talk to your doctor about the risks of using this medication for your condition.

What special precautions should I follow?

Before using fondaparinux injection,

  • tell your doctor and pharmacist if you have had a serious allergic reaction (difficulty breathing or swallowing or swelling of the face, throat, tongue, lips, or eyes) to fondaparinux. Your doctor will probably tell you not to use fondaparinux. Also tell your doctor if you are allergic to any other medications, or any of the ingredients in fondaparinux injection. Ask your pharmacist for a list of the ingredients. Also tell your doctor and pharmacist if you are allergic to latex.
  • tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Be sure to mention the medications listed in the IMPORTANT WARNING section. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
  • tell your doctor if you weigh 110 pounds (50 kg) or less, are bleeding anywhere on your body or have a low number of platelets (blood clotting cells) in your blood, endocarditis (an infection in the heart), or kidney disease. Your doctor will probably tell you not to use fondaparinux injection.
  • tell your doctor if you have or have ever had ulcers in your stomach or intestines, high blood pressure, a stroke or ministroke (TIA), eye disease due to diabetes, or liver disease. Also tell your doctor if you have recently had brain, eye, or spinal surgery.
  • tell your doctor if you are pregnant, plan to become pregnant, or are breastfeeding. If you become pregnant while taking fondaparinux injection, call your doctor.
  • if you are having surgery, including dental surgery, tell the doctor or dentist that you are taking fondaparinux injection.

What special dietary instructions should I follow?

Unless your doctor tells you otherwise, continue your normal diet.

What should I do if I forget a dose?

Give the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not use more than one dose of fondaparinux injection at the same time.

What side effects can this medication cause?

Fondaparinux injection may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

  • rash, itching, bruising, or bleeding at the injection site
  • dizziness
  • confusion
  • pale skin
  • blisters on skin
  • difficulty falling asleep or staying asleep

Some side effects can be serious. If you experience any of these symptoms, or those listed in the IMPORTANT WARNING section, call your doctor immediately or get emergency medical treatment:

  • unusual bleeding or bruising
  • dark red spots under the skin or in the mouth
  • hives
  • swelling of the face, throat, tongue, lips, or eyes
  • difficulty swallowing or breathing

Fondaparinux injection may cause other side effects. Call your doctor if you have any unusual problems while using this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online ( or by phone (1-800-332-1088).

What should I know about storage and disposal of this medication?

Your healthcare provider will tell you how to store your medication. Store your medication only as directed and out of reach of children. Make sure you understand how to store your medication properly. Do not freeze fondaparinux injection.

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach.

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website ( for more information if you do not have access to a take-back program.

In case of emergency/overdose

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

Symptoms of overdose may include the following:

  • bleeding

What other information should I know?

Before having any laboratory test, tell your doctor and the laboratory personnel that you are receiving fondaparinux injection.

Do not let anyone else use your medication. Ask your pharmacist any questions you have about refilling your prescription.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

Brand names

  • Arixtra®

Other names

  • Fondaparin sodium
Last Revised - 02/15/2018