Fondaparinux (also known by its brand name, Arixtra) is an anticoagulant (or blood thinner) that's used to prevent and treat blood clots in adults. It stops proteins in your body that typically help clot blood from working. Fondaparinux (Arixtra) is given as an injection under the skin once per day. The dosage typically depends on why you need fondaparinux (Arixtra) and your body weight. The most common side effect is bleeding.
Prevention of blood clots in the arms or legs (deep vein thrombosis or DVT) in people having stomach, hip, or knee surgery
Treatment of blood clots in the arms or legs (DVT) or in the lungs (pulmonary embolism or PE)
Fondaparinux (Arixtra) is an anticoagulant (or blood thinner). It blocks a protein called factor Xa that normally helps make clots and stop any bleeding. By blocking factor Xa, fondaparinux (Arixtra) helps prevent blood clots from forming in your body.
Source:Â DailyMed
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur:
More common
Pale skin
troubled breathing with exertion
unusual bleeding or bruising
unusual tiredness or weakness
Less common
Black, tarry stools
bladder pain
bleeding gums
blood in the urine or stools
blurred vision
chills
collection of blood under the skin
confusion
convulsions
decreased or cloudy urine
deep, dark purple bruise
difficult, burning, or painful urination
dizziness
fainting or lightheadedness when getting up from a lying or sitting position
frequent urge to urinate
increased thirst
irregular heartbeat
itching, pain, redness, or swelling at the injection site
loss of appetite
lower back or side pain
muscle pain or cramps
nausea or vomiting
numbness or tingling in the hands, feet, or lips
pinpoint red spots on the skin
red, tender, or oozing skin at incision
shortness of breath
sores, ulcers, or white spots on the lips or in the mouth
sudden sweating
Incidence not known
Back pain
bowel or bladder dysfunction
difficulty with swallowing
fast heartbeat
large, hive-like swelling on the face, eyelids, lips, tongue, throat, hands, legs, feet, or sex organs
leg weakness
numbness
paralysis
puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
tightness in the chest
Get emergency help immediately if any of the following symptoms of overdose occur:
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
More common
Difficulty having a bowel movement
swelling
trouble sleeping
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
Only need to use once a day
Good option if you have a history of heparin-induced thrombocytopenia (HIT) or can't use heparin for any other reason
Comes in prepackaged syringes for easy administration
Available as a lower-cost generic
Must inject into the skin, which can be uncomfortable
Can raise your risk for bleeding
Can't use to prevent clots if you weigh less than 110 lbs
Not a good option if you have severe kidney problems
No antidote (reversal agent) currently available, so serious bleeds from the medication might be harder to treat
Be sure to follow up with your provider so you can be properly monitored while you're taking fondaparinux (Arixtra). Also, set reminders for your daily fondaparinux (Arixtra) injections so you don't miss any doses. This will keep your risk for blood clots low.
Fondaparinux (Arixtra) can make it easier for you to bruise or bleed. It can also make it take longer for your body to stop any bleeding. Call your provider if you have any unusual bleeding (e.g., blood in urine or stool, coughing up blood, vomiting blood) or bruising while you're taking this medication.
Tell your providers and pharmacists about any medications that you're taking, especially if these medications are aspirin or other nonsteroidal anti-inflammatory drugs (NSAIDs) (e.g., ibuprofen (Advil), naproxen (Aleve)). Taking these medications with fondaparinux (Arixtra) can raise your risk for bleeding.
Let your surgeon or dentist know that you're taking fondaparinux (Arixtra) before any surgery or procedure gets scheduled. There might be specific instructions around the time of your scheduled procedure about when to stop using fondaparinux (Arixtra) to prevent serious bleeding complications.
Get medical help right away if you fall and hit your head hard, especially if you also feel dizzy or have a severe headache. You might need a head scan to see whether you have a brain bleed.
Tips for using fondaparinux (Arixtra) at home:
Carefully read the directions for use so you can inject fondaparinux (Arixtra) at home safely and properly. Ask your provider or pharmacist if you have any questions.
Make sure you know which strength and dose of fondaparinux (Arixtra) you have to prevent medication errors because the medication comes in many different strengths. Not using the proper strength or dose can raise your risk for blood clots or bleeding. Contact your provider or pharmacist if you're not sure of your dose.
Before you inject fondaparinux (Arixtra), always check to make sure the medication is clear and colorless. Don't use it if it's cloudy, discolored, or has many particles (solid chunks). Use a new fondaparinux (Arixtra) syringe, or call your provider or pharmacist to see whether you can get a replacement.
Inject fondaparinux (Arixtra) into the fat tissue under the skin of your stomach at least 2 inches away from your belly button. Always choose a different injection site for each dose. Repeated injections into the same area can cause pain and damaged skin. Never inject fondaparinux (Arixtra) into your muscle or vein.
After each fondaparinux (Arixtra) injection, throw away your used syringe and needle in a sharps container or something made of heavy-duty plastic (e.g., laundry detergent bottle). This lowers the risk of needle-stick injuries. Don't throw them away in your trash can. Learn more about how to throw away your sharps on the FDA's website.
Store fondaparinux (Arixtra) at room temperature. Don't put the medication into the refrigerator.
Fondaparinux (Arixtra) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Risk factors: Lumbar puncture (spinal tap) | Getting anesthesia near the spine (epidural or spinal anesthesia) | History of spinal surgery, spinal taps, spine problems, or epidurals | Taking nonsteroidal anti-inflammatory drugs (NSAIDs) or other blood thinners
You're at a greater risk of bleeding around your spinal cord if you're taking fondaparinux (Arixtra) and need to have a lumbar puncture (spinal tap) or get an epidural. Sometimes, this spinal bleeding can cause nerve damage and possibly make you paralyzed.
To lower this risk, your provider will tell you when to stop taking fondaparinux (Arixtra) before your planned back surgery or procedure. If it's not possible, make sure to be aware of the signs and symptoms of spinal problems. Call your provider right away if you notice pain along your spine; tingling, a burning sensation, numbness, or weakness in your legs; or that you can't urinate or have bowel movements as usual.
Risk factors: Taking other medications that raise the risk for bleeds | History of bleeding problems | Kidney problems | Eye problems related to diabetes | Stomach ulcer or other problems that can cause stomach bleeding | Severely high blood pressure | Recent surgery | Weight less than 110 lbs
Taking fondaparinux (Arixtra) can raise your risk for bleeds. Your risk can be even higher if you're also taking other medications that can cause bleeding, if you have certain medical conditions (e.g., kidney or bleeding problems), or if you weigh less than 110 lbs.
If you have a serious bleed from using fondaparinux (Arixtra), your provider will need to give you treatment to stop the bleed. Let your provider know if you have a fall, head injury, or other kinds of physical injury. Your provider might need to check you for bleeding inside your body. Get medical help right away if you have a severe headache, dark or tarry stool, bleeds that are difficult to stop, or any unusual bleeding or bruising.
Fondaparinux (Arixtra) can cause your platelet count to drop. Your provider will check your platelet count with routine blood tests. Your provider might stop the medication if your levels fall below a certain amount. Since platelets help with clotting, having a low platelet count can put you at risk for bleeding and easy bruising.
Look out for signs of bleeding, such as bleeding that doesn't stop; bleeding gums; vomit that's bloody or that looks like coffee grounds; or black, tarry stools. Get medical help right away if you experience any of these symptoms.
Prevention of DVT: The typical dose is 2.5 mg injected under the skin on your lower stomach once daily. How long you need to use the medication will depend on the type of surgery you're getting.
Treatment of DVT or PE: The dose depends on your weight.
Weight less than 110 lbs: The typical dose is 5 mg injected under the skin once daily.
Weight 110 lbs to 220 lbs: The typical dose is 7.5 mg injected under the skin once daily.
Weight greater than 220 lbs: The typical dose is 10 mg injected under the skin once daily.
Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Severe kidney problems
Active major bleeding (significant bleeding that's concerning)
Bacterial infection in the heart
Have low platelets and anti-platelet antibodies when fondaparinux (Arixtra) is in your system
Weight less than 110 lbs
Prevention of blood clots in the arms or legs (deep vein thrombosis or DVT) in people having stomach, hip, or knee surgery
Treatment of blood clots in the arms or legs (DVT) or in the lungs (pulmonary embolism or PE)
Lowering the risk of stroke and blood clots in with atrial fibrillation (AFib) that isn't caused by a heart valve problem
Treating blood clots in the legs (deep vein thrombosis (DVT)) or lungs (pulmonary embolism (PE))
Lowering the risk of blood clots from happening again in the legs (DVT) or lungs (PE) in certain people who are at high risk for clots
Preventing blood clots in the legs (DVT) or lungs (PE) in people who've had recent hip or knee surgery, those who are hospitalized, or those who were recently released from the hospital and are at high risk for blood clots
Lowering the risk of serious heart-related problems, such as heart attack or stroke, in people with coronary artery disease (CAD) when used together with aspirin
Lowering the risk of blood flow issues, major amputations, serious heart problems, or stroke in people with peripheral artery disease (PAD) when used together with aspirin
Treating blood clots and lowering the risk of blood clots from happening again after receiving at least 5 days of treatment with injectable blood thinner medications
Preventing blood clots in children ages 2 and older with a congenital heart disease (CHD) after a Fontan procedure.
Prevention of blood clots in the arms or legs (deep vein thrombosis or DVT) or in the lungs (pulmonary embolism or PE) in:
Treatment of blood clots
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