Fasenra Pen is a monoclonal antibody that affects the actions of the body's immune system. This medicine works by reducing levels of eosinophils, a certain type of white blood cell that may contribute to the symptoms of asthma.

Fasenra Pen is used together with other medicines to help control severe asthma in adults and children who are at least 12 years old. This medicine is for people whose asthma is not well controlled with other medications.

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

Before you receive Fasenra Pen, tell your doctor about all your medical conditions or allergies, all medicines you use, and if you are pregnant or breast-feeding.

Before you start treatment with Fasenra Pen, your doctor may perform tests to measure your eosinophil levels.

Fasenra Pen is injected under the skin. A healthcare provider will give you this injection, usually once every 4 weeks at first and then once every 8 weeks.

Follow your doctor's dosing instructions very carefully.

If you've been using a steroid medication, do not stop using it unless your doctor tells you to.

Fasenra Pen is not a rescue medicine for asthma attacks. Use only fast-acting inhalation medicine for an attack. Seek medical attention if your fast-acting medicine does not work.

You may need frequent medical tests to help your doctor determine how long to treat you with Fasenra Pen.

Asthma is often treated with a combination of drugs. Use all medications as directed and read all medication guides. Do not change your dose or dosing schedule without your doctor's advice. Your dose needs may change due to surgery, illness, stress, or a recent asthma attack. Tell your doctor if any of your medicines seem to stop working.

You should not be treated with Fasenra Pen if you are allergic to it.

Tell your doctor if you have ever had:

• a parasite infection (such as roundworms or tapeworms); or

• if you use an oral or inhaled steroid medication.

Follow your doctor's instructions about receiving Fasenra Pen if you are pregnant. Not treating asthma during pregnancy could harm both mother and baby. Tell your doctor if you are pregnant or plan to become pregnant.

It may not be safe to breast-feed a baby while you are using this medicine. Ask your doctor about any risks.

Fasenra Pen should not be given to a child younger than 12 years old.

Call your doctor for instructions if you miss an appointment for your Fasenra Pen.

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

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

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

Fasenra Pen may cause serious side effects. Call your doctor at once if you have:

• new or worsening asthma symptoms.

Common side effects of Fasenra Pen may include:

• sore throat; or

• headache.

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.

Other drugs may affect Fasenra Pen, 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.