Mepolizumab Injection

Mepolizumab is a medication that treats severe asthma. This condition causes your airways to narrow and swell. Mepolizumab can also treat condition that cause a high eosinophil count, which are a type of white blood cell. A healthcare provider can give you this injection or they can teach you how to give it to yourself at home.

What is this medication?

MEPOLIZUMAB (me poe LIZ ue mab) prevents the symptoms of asthma. It is prescribed when other medications have not worked well enough. It may also be used to treat other immune system disorders. It works by decreasing the amount of certain white blood cells (eosinophils) in your body. This helps decrease inflammation. Do not use it to treat a sudden asthma attack. It is a monoclonal antibody.

This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions.



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What should I tell my care team before I take this medication?

They need to know if you have any of these conditions:

  • Parasitic (helminth) infection
  • An unusual or allergic reaction to mepolizumab, hamster proteins, other medications, foods, dyes, or preservatives
  • Pregnant or trying to get pregnant
  • Breast-feeding

How should I use this medication?

This medication is injected under the skin. It is usually given by your care team in a hospital or clinic setting.

If you get this medication at home, you will be taught how to prepare and give it. Take it as directed on the prescription label. Keep taking it unless your care team tells you to stop.

If you use a pen, be sure to take off the outer needle cover before using the dose. It is important that you put your used needles and syringes in a special sharps container. Do not put them in a trash can. If you do not have a sharps container, call your pharmacist or care team to get one.

This medication comes with INSTRUCTIONS FOR USE. Ask your pharmacist for directions on how to use this medication. Read the information carefully. Talk to your pharmacist or care team if you have questions.

Talk to your care team about the use of this medication in children. While it may be prescribed for children as young as 6 years for selected conditions, precautions do apply.

Overdosage: If you think you have taken too much of this medicine contact a poison control center or emergency room at once.

NOTE: This medicine is only for you. Do not share this medicine with others.


What if I miss a dose?

If you get this medication at the hospital or clinic: It is important not to miss your dose. Call your care team if you are unable to keep an appointment.

If you give yourself this medication at home: If you miss a dose, take it as soon as you can. Then continue your normal schedule. If it is almost time for your next dose, take only that dose. Do not take double or extra doses. Call your care team with questions.

What may interact with this medication?

Interactions are not expected.

This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.


What should I watch for while using this medication?

Visit your care team for regular checks on your progress. Tell your care team if your symptoms do not start to get better or if they get worse.

Talk with your care team if you have not had chickenpox or the vaccine for chickenpox.

Do not stop taking your other asthma medications unless instructed to do so by your care team.

Your condition will be monitored carefully while you are receiving this medication.

What side effects may I notice from receiving this medication?

Side effects that you should report to your care team as soon as possible:

  • Allergic reactions or angioedema—skin rash, itching or hives, swelling of the face, eyes, lips, tongue, arms, or legs, trouble swallowing or breathing

Side effects that usually do not require medical attention (report to your care team if they continue or are bothersome):

  • Back pain
  • Fatigue
  • Headache
  • Joint pain
  • Pain, redness, or irritation at injection site
  • Sore throat

This list may not describe all possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Where should I keep my medication?

Keep out of the reach of children and pets.

Store in a refrigerator or at room temperature between 15 and 30 degrees C (59 and 86 degrees F).

Refrigeration (preferred): Store it in the refrigerator. Keep it in the original carton until you are ready to take it. Remove the dose from the carton about 30 minutes before it is time for you to take it. Use it within 8 hours of removing it from the carton. If the dose is out of the carton for more than 8 hours, get rid of it. Get rid of any unused medication after the expiration date.

Room Temperature: This medication may be stored at room temperature for up to 7 days. Keep it in the original carton until you are ready to take it. Once removed from the carton, it must be used within 8 hours. If it is out of the carton for more than 8 hours, get rid of it. If it is stored at room temperature, get rid of any unused medication after 7 days or after it expires, whichever is first.

To get rid of medication that are no longer needed or have expired:

  • Take the medication to a medication take-back program. Check with your pharmacy or law enforcement to find a location.
  • If you cannot return the medication, ask your pharmacist or care team how to get rid of this medication safely.

NOTE: This sheet is a summary. It may not cover all possible information. If you have questions about this medicine, talk to your doctor, pharmacist, or health care provider.

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Note: Introduction and Additional Common Questions written and medically approved by Cleveland Clinic professionals.

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