Alglucosidase alfa helps replace an enzyme that is missing in people with a certain genetic disorder.

Alglucosidase alfa is used to treat a glycogen storage disorder called Pompe disease, (also called GAA deficiency) in adults and children.

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

Tell your doctor if you have ever had:

• heart disease; or
• lung disease or breathing disorder.

Babies who develop Pompe disease in the first year of life may need specialized medical tests to improve treatment with alglucosidase alfa treatment.

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

You should not breastfeed within 24 hours after receiving alglucosidase alfa. If you use a breast pump during this time, throw out any milk you collect. Do not feed it to your baby.

Your name may be listed on the Pompe Registry. This is to track the progress of your disease and the outcome of your treatment with alglucosidase alfa.

Use Myozyme (Intravenous) exactly as directed on the label, or as prescribed by your doctor. Do not use in larger or smaller amounts or for longer than recommended.

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Some allergic reactions may occur during the injection, or as long as 3 hours afterward. Tell your caregivers or get emergency medical help right away if you have:

• a feeling like you might pass out, even while lying down;
• slow heart rate, weak pulse, fainting, slow breathing (breathing may stop);
• bronchospasm (wheezing, tight feeling in your chest or throat, trouble breathing);
• pale skin, cold or clammy skin, blue lips or fingernails, cold hands or feet;
• warmth, redness, numbness, or tingly feeling under your skin;
• rash, itching, sweating, fever;
• severe headache, nausea, feeling restless or nervous;
• seizure (convulsions); or
• fast heart rate, pounding in your neck or ears, anxiety, confusion.

Also call your doctor at once if you have:

• skin changes (sores, lesions, ulcers, discoloring); or
• puffy eyes, swelling in your ankles or feet, weight gain, urine that looks foamy.

Common side effects may include:

• hives; difficult breathing; swelling of your face, lips, tongue, or throat;
• pale skin, blue lips, feeling hot or feverish;
• skin rash, itching, flushing (warmth, redness, or tingly feeling);
• headache, dizziness, agitation, muscle twitching;
• fast heart rate, rapid breathing, chest discomfort, cough;
• increased blood pressure;
• nausea, vomiting;
• tremor, shaking, increased sweating; or
• muscle pain, tiredness.

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.

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