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Generic Name: mepolizumab (MEP oh LIZ ue mab)
Brand Name: Nucala, Nucala Prefilled Autoinjector, Nucala Prefilled Syringe

Medically reviewed by on Jun 14, 2019 – Written by Cerner Multum

What is mepolizumab?

Mepolizumab is a monoclonal antibody that works by reducing levels of a certain type of white blood cell that may contribute to certain disorders.

Mepolizumab is used together with other medicines to help control severe asthma in adults and children who are at least 12 years old.

Mepolizumab is also used in adults to help control symptoms and reduce flares of a rare autoimmune disorder called eosinophilic granulomatosis with polyangiitis (EPGA).

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

Important Information

Follow all directions on your medicine label and package. Tell each of your healthcare providers about all your medical conditions, allergies, and all medicines you use.

Before taking this medicine

You should not use mepolizumab if you are allergic to it.

Mepolizumab is not approved for use by anyone younger than 12 years old. Mepolizumab should not be used to treat EPGA in anyone younger than 18 years old.

Tell your doctor if:

  • you also use steroid asthma medication;

  • you have a history of parasite infection (such as roundworms or tapeworms);

  • you have a history of herpes zoster (also called shingles); or

  • you have never had chickenpox or received a chickenpox (varicella) vaccine.

You may be given a zoster vaccine before you start using mepolizumab.

If you also use an oral or inhaled steroid medication, you should not stop using it suddenly. Follow your doctor's instructions about tapering your dose.

Tell your doctor if you are pregnant. Your name may be listed on a pregnancy registry to track the effects of mepolizumab on the baby.

It may not be safe to breastfeed while using mepolizumab. Ask your doctor about any risk.

How is mepolizumab given?

Mepolizumab is not a rescue medicine for asthma attacks. Use only fast-acting inhalation medicine for an attack. Seek medical attention if your breathing problems get worse quickly, or if you think your asthma medications are not working as well.

Your doctor may perform blood tests to make sure you do not have conditions that would prevent you from safely using mepolizumab.

Mepolizumab is injected under the skin, usually once every 4 weeks. A healthcare provider may teach you how to properly use the medication by yourself. Follow all directions on your prescription label

Mepolizumab must be mixed with a liquid (diluent) before using it. Read and carefully follow any Instructions for Use provided with your medicine. When using injections by yourself, be sure you understand how to properly mix and store the medicine.

Gently swirl but do not shake the mixed medicine. Prepare an injection only when you are ready to give it. Do not use if the medicine has changed colors or has particles in it. Call your pharmacist for new medicine.

Store the vial (bottle) in its original carton at room temperature. Protect from light and do not freeze.

Store the prefilled syringe or autoinjector in the original carton in a refrigerator. Do not freeze or shake the medicine. After opening a carton, you must use the syringe or autoinjector within 8 hours.

You may store the prefilled syringe or autoinjector in the unopened carton at room temperature for up to 7 days. Throw away a syringe or autoinjector left out of the refrigerator for more than 7 days.

Each vial, prefilled syringe, or autoinjector is for one use only. Throw it away after one use, even if there is still medicine left inside.

Use a needle and syringe only once and then place them in a puncture-proof "sharps" container. Follow state or local laws about how to dispose of this container. Keep it out of the reach of children and pets.

What happens if I miss a dose?

Call your doctor for instructions if you miss a dose of mepolizumab.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while using mepolizumab?

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

Mepolizumab side effects

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

Call your doctor at once if you have:

  • unusual pain or tiredness;

  • burning or tingling anywhere in your body; or

  • a red or blistering skin rash.

Common side effects may include:

  • headache;

  • feeling tired;

  • back pain; or

  • pain, swelling, redness, burning, or itching where the medicine was injected.

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.

Mepolizumab dosing information

Usual Adult Dose for Asthma -- Maintenance:

100 mg subcutaneously every 4 weeks

-This drug should be administered in the upper arm, thigh, or abdomen.

Use: Add-on maintenance treatment for severe asthma with an eosinophilic phenotype

Usual Adult Dose for Wegener's Granulomatosis:

300 mg (as 3 separate 100 mg injections) subcutaneously every 4 weeks

-This drug should be administered in the upper arm, thigh, or abdomen as 3 separate 100 mg injections at least 5 cm (approximately 2 inches) apart if more than 1 injection is administered at the same site.

Use: For eosinophilic granulomatosis with polyangiitis (EGPA)

Usual Pediatric Dose for Asthma -- Maintenance:

6 to 12 years:
40 mg subcutaneously every 4 weeks

12 years or older:
100 mg subcutaneously every 4 weeks

-This drug should be administered in the upper arm, thigh, or abdomen.

Use: Add-on maintenance therapy for severe asthma with an eosinophilic phenotype in children 6 years and older

What other drugs will affect mepolizumab?

Other drugs may affect mepolizumab, 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.

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