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Idelvion Side Effects

Generic Name: coagulation factor ix

Note: This document contains side effect information about coagulation factor ix. Some of the dosage forms listed on this page may not apply to the brand name Idelvion.

For the Consumer

Applies to coagulation factor ix: intravenous powder for solution

Side effects requiring immediate medical attention

Along with its needed effects, coagulation factor ix (the active ingredient contained in Idelvion) 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 or nurse immediately if any of the following side effects occur while taking coagulation factor ix:

Incidence not known

  • Anxiety
  • blurred vision
  • burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings
  • chest pain
  • confusion
  • cough
  • difficult or labored breathing
  • difficulty with swallowing
  • dizziness or lightheadedness
  • dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
  • fainting
  • fast heartbeat
  • hives, itching, or skin rash
  • large, hive-like swelling on the face, eyelids, lips, tongue, throat, hands, legs, feet, or sex organs
  • nausea
  • pains in the chest, groin, or legs, especially calves of the legs
  • puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
  • restlessness
  • severe headaches of sudden onset
  • sudden loss of coordination
  • sudden onset of shortness of breath for no apparent reason
  • sudden onset of slurred speech
  • sudden shortness of breath or troubled breathing
  • sudden vision changes
  • sweating
  • tenderness, pain, swelling, warmth, skin discoloration, and prominent superficial veins over affected area
  • tightness in the chest
  • unusual drowsiness, dullness, tiredness, weakness, or feeling of sluggishness
  • unusual tiredness or weakness
  • vomiting

Side effects not requiring immediate medical attention

Some side effects of coagulation factor ix 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:

Less common

  • Change in taste
  • loss of taste
  • headache
  • pain in the arms or legs

For Healthcare Professionals

Applies to coagulation factor ix: intravenous kit, intravenous powder for injection


Frequency not reported: Hypersensitivity (including bronchospastic reactions and/or hypotension, anaphylaxis, development of high-titer inhibitors necessitating alternative treatment)[Ref]


Common (1% to 10%): Factor IX inhibition[Ref]


Common (1% to 10%): Nausea, vomiting[Ref]


Common (1% to 10%): Rash pruritic, hives[Ref]


Common (1% to 10%): Injection site discomfort, injection site pain[Ref]

Nervous system

Common (1% to 10%): Headache, dysgeusia, lethargy, dizziness, shaking, drowsiness[Ref]


Common (1% to 10%): Dry cough, hypoxia, chest tightness, dyspnea[Ref]


The renal infarct occurred in a hepatitis C antibody positive patients 12 days after treatment of a bleeding episode; the relation of the infarct to the prior administration of this drug is uncertain.[Ref]

Common (1% to 10%): Renal infarct[Ref]


Common (1% to 10%): Blurred vision[Ref]


Common (1% to 10%): Influenza, cellulitis at injection site, phlebitis at injection site[Ref]


Common (1% to 10%): Apathy, depression[Ref]


Common (1% to 10%): Hemophilia (lack of efficacy), asthenia, fever, chills[Ref]


Common (1% to 10%): Flushing[Ref]


1. "Product Information. BeneFIX (coagulation factor IX)." Wyeth Laboratories, Philadelphia, PA.

2. "Product Information. Ixinity (coagulation factor IX)." Cangene bioPharma, Inc., Baltimore, MD.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.