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Kalbitor Side Effects

Generic name: ecallantide

Medically reviewed by Last updated on Aug 27, 2020.

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

In Summary

More frequent side effects include: pruritus. See below for a comprehensive list of adverse effects.

For the Consumer

Applies to ecallantide: subcutaneous solution


Subcutaneous route (Solution)

Anaphylaxis has been reported after administration of ecallantide. Because of this risk, ecallantide should only be administered by a healthcare professional who is aware of the similarity of symptoms between anaphylaxis and hereditary angioedema and who has the appropriate medical support to manage both conditions. Patients should be monitored closely.

Side effects requiring immediate medical attention

Along with its needed effects, ecallantide (the active ingredient contained in Kalbitor) 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 ecallantide:

Less common

  • Blurred vision
  • chest discomfort
  • confusion
  • cough
  • difficulty with breathing
  • difficulty with swallowing
  • dizziness
  • dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
  • fast heartbeat
  • feeling of warmth
  • fever
  • hives or welts, itching, or skin rash
  • puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
  • redness of the face, neck, arms, and occasionally, upper chest
  • redness of the skin
  • runny nose
  • sneezing
  • stuffy nose
  • sweating
  • throat irritation
  • tightness in the chest
  • unusual tiredness or weakness

Side effects not requiring immediate medical attention

Some side effects of ecallantide 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

Less common

  • Bleeding, blistering, burning, coldness, discoloration of the skin, feeling of pressure, hives, infection, inflammation, itching, lumps, numbness, pain, rash, redness, scarring, soreness, stinging, swelling, tenderness, tingling, ulceration, or warmth at the injection site
  • muscle aches
  • nausea
  • sore throat

For Healthcare Professionals

Applies to ecallantide: subcutaneous solution


The most common adverse reactions were headache, nausea, diarrhea, pyrexia, injection site reactions, and nasopharyngitis.[Ref]


Common (1% to 10%): Pruritus, rash, urticaria[Ref]


Very common (10% or more): Nausea (up to 13%), diarrhea (up to 11%)

Common (1% to 10%): Vomiting, upper abdominal pain[Ref]


Common (1% to 10%): Anaphylaxis

Frequency not reported: Hypersensitivity reactions[Ref]


Common (1% to 10%): Injection site reactions[Ref]

Nervous system

Very common (10% or more): Headache (up to 16%)[Ref]


Very common (10% or more): Fatigue (12%)[Ref]


Common (1% to 10%): Upper respiratory tract infection, nasopharyngitis[Ref]

Frequently asked questions


1. "Product Information. Kalbitor (ecallantide)." Dyax Corporation, Cambridge, MA.

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.