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Elaprase Side Effects

Generic name: idursulfase

Medically reviewed by Last updated on May 16, 2023.

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

Applies to idursulfase: intravenous solution.


Intravenous route (Solution)

Life-threatening anaphylactic reactions, presenting as respiratory distress, hypoxia, hypotension, urticaria, and/or angioedema of throat or tongue have occurred in some patients during and up to 24 hours after idursulfase infusions, regardless of duration of the course of treatment. Closely observe patients during and after idursulfase administration and be prepared to manage anaphylaxis. Inform patients of the signs and symptoms of anaphylaxis and have them seek immediate medical care should symptoms occur. Patients with compromised respiratory function or acute respiratory disease may be at risk of serious acute exacerbation of their respiratory compromise due to hypersensitivity reactions, and require additional monitoring.

Serious side effects of Elaprase

Along with its needed effects, idursulfase (the active ingredient contained in Elaprase) 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 idursulfase:

More common

Less common

Incidence not known

Other side effects of Elaprase

Some side effects of idursulfase 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

For Healthcare Professionals

Applies to idursulfase: intravenous solution.


The most frequently reported adverse effects in all clinical trials were hypersensitivity reactions and included rash, urticaria, pruritus, flushing, pyrexia, and headache.

The most frequently reported adverse effects following treatment were hypoxia, pyrexia, rash, vomiting, diarrhea, cough, musculoskeletal pain, headache, pruritus, and urticaria.[Ref]


Very common (10% or more): Hypersensitivity reaction

Frequency not reported: Anaphylactoid/anaphylactic reaction

Postmarketing reports: Late-emergent anaphylactoid reaction[Ref]

In clinical trials, the most common adverse effects were hypersensitivity reactions and included rash, urticaria, pruritus, flushing, pyrexia, and headache. Most reactions were resolved with slowing the infusion rate or temporarily stopping the infusion, with or without additional treatments including antihistamines and/or corticosteroids prior to or during infusions.[Ref]


In clinical trials, 32 out of 63 patients 5 years and older tested positive for antidrug antibodies at least 1 time; of the 32 patients, 23 tested positive for antidrug antibodies 3 or more times. The incidence of hypersensitivity reactions was higher in positive antidrug antibody patients than those who tested negative. Out of 32 antidrug antibody positive patients, 13 also tested positive for neutralizing antibodies. There was no clear relationship between presence of either type of antibody and therapeutic response.[Ref]

Very common (10% or more): Antidrug antibody development (50%), neutralizing antibody development (24.3%)[Ref]

Nervous system

Very common (10% or more): Headache (up to 65.6%)

Common (1% to 10%): Dizziness, tremor[Ref]


Very common (10% or more): Rash (up to 34.4%), pruritus (up to 31.3%), urticaria (up to 16%)

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


The most serious infusion-related reactions included anaphylactoid/anaphylactic reactions. The most common infusion-related reactions included cutaneous reactions (rash, pruritus, urticaria), pyrexia, headache, hypertension, flushing, wheezing, hypoxia, dyspnea, abdominal pain, nausea, dyspepsia, chest pain, and infusion site swelling. Treatment/amelioration of infusion-related reactions included slowing the infusion rate, interrupting the infusion, or drug therapy (e.g., antihistamines, antipyretics, low-dose corticosteroids [prednisone, methylprednisolone], beta-agonist nebulization).[Ref]

Very common (10% or more): Infusion-related reaction (68.8%), pyrexia (up to 62.5%), chest pain (up to 15.6%), infusion site swelling (12.5%)

Common (1% to 10%): Face edema, peripheral edema[Ref]


Very common (10% or more): Musculoskeletal pain (13%)

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


Very common (10% or more): Abdominal pain (up to 53.1%), nausea (up to 28.1%), dyspepsia (12.5%), vomiting, diarrhea

Common (1% to 10%): Swollen tongue[Ref]


Very common (10% or more): Hypertension (up to 25%), flushing (15.6%)

Common (1% to 10%): Cyanosis, arrhythmia, tachycardia, hypotension

Postmarketing reports: Cardiac failure, cardiorespiratory arrest[Ref]


Very common (10% or more): Wheezing (15.6%), dyspnea (up to 12.5%)

Common (1% to 10%): Cough, bronchospasm, tachypnea, hypoxia

Frequency not reported: Pulmonary embolism

Postmarketing reports: Respiratory failure, respiratory distress, pneumonia[Ref]


1. Cerner Multum, Inc. UK Summary of Product Characteristics.

2. Product Information. Elaprase (idursulfase). Shire US Inc. 2006.

3. Cerner Multum, Inc. Australian Product Information.

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.