This medication is used along with other medications to control and prevent symptoms (such as wheezing and shortness of breath) caused by asthma. Controlling symptoms of asthma helps you do your normal activities and decreases time lost from work or school. Mepolizumab is also used to treat certain other immune system disorders (chronic rhinosinusitis with nasal polyps, eosinophilic granulomatosis with polyangiitis, hypereosinophilic syndrome). This medication works by decreasing a certain type of white blood cell (eosinophils). This effect helps reduce swelling (inflammation) of the airways to make breathing easier. It may also help reduce the size of nasal polyps, and lessen symptoms such as runny/stuffy nose, mucus in the throat, loss of smell, facial pain, and tiredness.

This medication must be used regularly to be effective. It does not work right away and should not be used to relieve sudden asthma attacks or breathing problems. If an asthma attack occurs, use your quick-relief inhaler as prescribed.

Read the Patient Information Leaflet and Instructions for Use if available from your pharmacist before you start using mepolizumab and each time you get a refill. Ask your health care professional how to prepare and use this medication. If you have any questions, ask your doctor or pharmacist.

Inject this medication under the skin as directed by your doctor, usually once every 4 weeks. The injection is given in the upper arm, thigh, or abdomen. The dosage is based on your age, medical condition, and response to treatment.

If you are using the syringe/autoinjector, take it out of the refrigerator at least 30 minutes before you inject it to allow it to reach room temperature. Do not warm up this medication any other way (for example, do not heat it in the microwave or place it in hot water). Do not shake the medication. Before using, check this product for particles or discoloration. If either is present, do not use the liquid. Before injecting each dose, clean the skin you are going to inject into (the injection site) with rubbing alcohol. Change the injection site each time to lessen injury under the skin. Do not inject into skin that is tender, bruised, red, or hard. To lessen bruising, do not rub the injection site after a shot. Learn how to store and discard medical supplies safely.

If you are regularly using a corticosteroid medication, you should not stop using it unless directed by your doctor. Some conditions (such as asthma, allergies) may become worse when the drug is suddenly stopped. If you suddenly stop using the corticosteroid medication, you may also have withdrawal symptoms (such as weakness, weight loss, nausea, muscle pain, headache, tiredness, dizziness). To help prevent withdrawal, your doctor may slowly lower the dose of your corticosteroid medication after you begin using mepolizumab. Tell your doctor or pharmacist right away if you have withdrawal.

Use this medication regularly to get the most benefit from it. To help you remember, mark your calendar with a reminder.

Tell your doctor if your condition does not get better or if it gets worse.

Pain/redness/swelling at injection site or headache may occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly.

Remember that this medication has been prescribed because your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

Tell your doctor right away if you have any serious side effects, including:

• muscle ache/pain/spasms

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including:

• rash
• itching/swelling (especially of the face/tongue/throat)
• severe dizziness
• trouble breathing

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US - Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

Before using mepolizumab, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history, especially of:

• infection due to a parasite

Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).

During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.

It is unknown if this medication passes into breast milk. Consult your doctor before breastfeeding.

Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.

If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call 1-800-222-1222. Canada residents can call 1-844-764-7669.

Do not share this medication with others.

Keep all medical and lab appointments.

If you miss a dose, use it as soon as you remember. If it is near the time of the next dose, skip the missed dose. Use your next dose at the regular time. Do not double the dose to catch up.

Store the syringe/autoinjector in the refrigerator. Do not freeze. Keep the medication in the original package to protect from light. The unopened carton may also be stored at room temperature if needed. If the unopened carton is stored at room temperature, discard the medication after 7 days. Once the syringe/autoinjector is removed from the carton, the medication expires after 8 hours. Keep all medications away from children and pets.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.