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Generic Name: laronidase (lar ON i dase)
Brand Name: Aldurazyme

Medically reviewed on December 15, 2017

What is laronidase?

Laronidase contains an enzyme that occurs naturally in the body in healthy people. Some people lack this enzyme because of a genetic disorder. Laronidase helps replace this missing enzyme in such people.

Laronidase is used to treat some of the symptoms of a genetic condition called mucopolysaccharidosis (MYOO-koe-pol-ee-SAK-a-rye-DOE-sis) or MPS I, also called Hurler syndrome, Hurler-Scheie syndrome, or Scheie syndrome.

MPS I is a metabolic disorder in which the body lacks the enzyme needed to break down certain substances. These substances can build up in the body, causing enlarged organs, abnormal bone structure, changes in facial features, breathing problems, heart problems, vision or hearing loss, and changes in mental or physical abilities.

Laronidase may improve breathing and walking ability in people with this condition. However, this medication is not a cure for MPS I.

Laronidase may also be used for purposes not listed in this medication guide.

Important Information

An allergic reaction may occur during or shortly after infusion of this medicine. Tell your caregivers or get emergency medical help right away if you have any signs of a severe allergic reaction, such as sweating, trouble breathing, pale skin, blue lips or fingernails, and feeling like you might pass out.

Before taking this medicine

You should not be treated with laronidase if you are allergic to it. Your laronidase infusion may be delayed if you have a fever or cold symptoms.

To make sure laronidase is safe for you, tell your doctor if you have ever had:

  • breathing problems;

  • heart disease; or

  • sleep apnea, and you use a continuous positive airway pressure (CPAP) machine.

It is not known whether this medicine will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant.

If you are pregnant, your name may be listed on a pregnancy registry. This is to track the outcome of the pregnancy and to evaluate any effects of laronidase on the baby.

It is not known whether laronidase passes into breast milk or if it could affect the nursing baby. Tell your doctor if you are breast-feeding.

How is laronidase given?

Laronidase is injected into a vein through an IV. A healthcare provider will give you this injection.

Laronidase is usually given once per week.

Tell your doctor if you have been sick with a fever or cold. You may need to wait until you get better before receiving your dose of laronidase.

Laronidase must be given slowly, and the IV infusion can take up to 4 hours to complete.

An hour before each injection, you will be given other medications to help prevent a serious allergic reaction.

After each injection, you will be watched closely for 60 minutes or longer to make sure you do not have an allergic reaction.

Your doctor will need to check your progress on a regular basis while you are using laronidase.

It may take up to several months to years before you get the full benefit of treatment with laronidase. Keep receiving your injections as directed and tell your doctor if your symptoms do not improve or if they get worse.

Your name may need to be listed on a MPS I Registry while you are using this medicine. The purpose of this registry is to track the progression of this disorder and the effects that laronidase has in long-term treatment.

What happens if I miss a dose?

Call your doctor for instructions if you miss an appointment for your laronidase injection.

What happens if I overdose?

Since laronidase is given by a healthcare professional in a medical setting, an overdose is unlikely to occur.

What should I avoid while receiving laronidase?

Follow your doctor's instructions about any restrictions on food, beverages, or activity.

Laronidase side effects

Get emergency medical help if you have signs of an allergic reaction: hives; wheezing, difficult breathing; slow heartbeats; feeling like you might pass out; swelling of your face, lips, tongue, or throat.

An allergic reaction may occur during or shortly after infusion of this medicine (up to 3 hours later). Tell your caregivers or get emergency medical help right away if you have any signs of a severe allergic reaction, such as:

  • rapid breathing, or feeling short of breath;

  • wheezing, chest tightness;

  • feeling like you might pass out, even while lying down;

  • fast or slow heartbeats;

  • sweating, cold or clammy skin;

  • pale skin; or

  • blue lips or fingernails.

Common side effects may include:

  • fever, chills;

  • cold symptoms such as stuffy nose, sneezing, sore throat;

  • increased blood pressure;

  • warmth, redness, numbness, or tingly feeling;

  • fast heartbeats;

  • overactive reflexes; or

  • pain, swelling, burning, or irritation around the IV needle.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

See also: Side effects (in more detail)

What other drugs will affect laronidase?

Other drugs may interact with laronidase, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell your doctor about all your current medicines and any medicine you start or stop using.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

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