Nucala (Mepolizumab) - Subcutaneous

What Is Nucala?

Nucala (mepolizumab) is an injectable prescription medication used to treat certain types of severe asthma and chronic rhinosinusitis with nasal polyps. It also helps treat certain blood disorders involving high levels of eosinophils (a type of white blood cell). Nucala is not a rescue medication and will not treat a sudden asthma attack or breathing problems.

Nucala belongs to a group of drugs called monoclonal antibodies. It works by decreasing levels of eosinophils, which contribute to inflammation.

Nucala is injected under your skin (subcutaneously). Your healthcare provider may administer your dose in the office or teach you how to inject it yourself.

Drug Facts

Generic Name: Mepolizumab

Brand Name: Nucala

Drug Availability: Prescription

Therapeutic Classification: Monoclonal antibody

Available Generically: No

Controlled Substance: N/A

Administration Route: Subcutaneous

Active Ingredient: Mepolizumab

Dosage Form(s): Prefilled syringe, auto-injector, solution for injection

What Is Nucala Used For?

The FDA has approved Nucala to treat the following conditions:

How to Take Nucala

Nucala is injected under your skin (subcutaneously) every four weeks. Your healthcare provider may give you your first dose in the office to monitor you for side effects. You may continue to receive your doses in the office, or your healthcare provider may teach you how to administer Nucala. Nucala is available as a single-dose prefilled syringe or auto-injector for at-home administration, so you don't need to draw up your dose from a vial.

If you self-administer Nucala, follow these steps to ensure you receive your dose safely:

  • Remove your prefilled syringe or auto-injector from the refrigerator, and let it sit at room temperature for 30 minutes (not in direct sunlight). This will help reduce discomfort. Do not remove the clear needle cap yet.
  • Do not shake your syringe or auto-injector.
  • Do not use if your solution appears cloudy, has particles or is leaking.
  • Do not use if your syringe or auto-injector looks damaged or if you have dropped it onto a hard surface.
  • Wash your hands with soap and water before administering your dose.
  • Clean your chosen injection site with an alcohol swab.
  • Following your healthcare provider's instructions, inject Nucala into your upper thigh or stomach. Nucala may also be injected into your upper arm if someone else administers your dose. Do not inject Nucala within two inches of your belly button. 
  • Change your injection site each time to lessen injury under the skin.
  • Do not inject Nucala into bruised, tender, red or hard skin.
  • Do not rub your injection site after injecting your dose. This can affect how the medication is absorbed into your body.
  • If your dose requires more than one injection, separate your injection sites by at least two inches.
  • Only use each syringe or auto-injector once. Throw it away after each use, even if there's still medicine left inside.

Storage

Keep Nucala in the refrigerator in its original carton, protected from light. You may store unopened cartons at room temperature for up to seven days if you need. Once you remove the prefilled syringe or auto-injector from the carton, you must use it within eight hours. Keep Nucala and all of your medicines out of the reach of children and pets.

How Long Does Nucala Take to Work?

Nucala takes time to work. If you're using Nucala for asthma, you may notice improvements in your symptoms within the first three months of treatment. Nucala is not a rescue medication and will not treat an asthma attack. Talk with your healthcare provider about which medications to use during an asthma attack.

What Are the Side Effects of Nucala?

This is not a complete list of side effects and others may occur. A healthcare provider can advise you on side effects. If you experience other effects, contact your pharmacist or a healthcare provider. You may report side effects to the FDA at fda.gov/medwatch or 1-800-FDA-1088.

Common Side Effects

You may develop side effects from Nucala. Be sure to let your healthcare provider know if you experience any side effects that bother you or that don't go away.

Common side effects include:

  • Headache
  • Pain, redness, swelling, itching or burning at the injection site
  • Back pain
  • Tiredness

If you take Nucala to treat chronic rhinosinusitis with nasal polyps, you may also experience pain in your mouth, throat or joints.

Severe Side Effects

Nucala may rarely cause serious side effects. Call your healthcare provider right away if you develop any severe reactions. Call 911 if your symptoms feel life-threatening or you think you are having a medical emergency. Serious side effects include:

Allergic reactions, including a severe form called anaphylaxis. Allergic reactions can happen hours to days after receiving Nucala. Symptoms of an allergic reaction include:

  • Difficulty breathing
  • Rash or hives
  • Fainting, dizziness or feeling lightheaded
  • Swelling of your face, mouth or tongue

Herpes zoster infections have occurred in patients receiving Nucala, which can cause shingles. Ask your healthcare provider if you should receive a shingles vaccine before starting Nucala treatment.

Report Side Effects

Nucala may cause other side effects. Call your healthcare provider if you have any unusual problems while taking this medication. 

If you experience a serious side effect, you or your provider may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting Program or by phone (800-332-1088).

Dosage: How Much Nucala Should I Take?

Drug Content Provided and Reviewed by IBM Micromedex®

The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

  • For injection dosage forms (prefilled syringe or prefilled autoinjector):
    • For severe asthma:
      • Adults and children 12 years of age and older—100 milligrams (mg) injected under your skin once every 4 weeks.
      • Children 6 to 11 years of age—40 mg injected under your skin once every 4 weeks.
      • Children younger than 6 years of age—Use and dose must be determined by your doctor.
    • For CRSwNP:
      • Adults—100 milligrams (mg) injected under your skin once every 4 weeks.
      • Children—Use and dose must be determined by your doctor.
    • For EGPA:
      • Adults—300 milligrams (mg) injected under your skin once every 4 weeks (given as 3 separate 100 mg injections injected 5 cm apart if given at the same injection site).
      • Children—Use and dose must be determined by your doctor.
    • For HES:
      • Adults and children 12 years of age and older—300 milligrams (mg) injected under your skin once every 4 weeks (given as 3 separate 100 mg injections injected 5 cm apart if given at the same injection site).
      • Children younger than 12 years of age—Use and dose must be determined by your doctor.

Modifications

Pregnancy: Animal studies of Nucala use during pregnancy didn't find harmful effects, but studies in humans are lacking. You and your healthcare provider must weigh the risks and benefits of using Nucala during pregnancy.

Lactation: Nucala is likely excreted in breastmilk, but the effects of Nucala on a breastfed baby are unknown. Talk with your healthcare provider about the best way forward.

Pediatric use: The FDA has approved Nucala to treat children six years and older with severe asthma and 12 years and older with hypereosinophilic syndrome (HES). The safety and effectiveness of using Nucala to treat people younger than 18 with chronic rhinosinusitis with nasal polyps or eosinophilic granulomatosis with polyangiitis are unknown.

Adults over 65 years: Older adults do not require a different dose of Nucala compared to younger adults, but some patients over the age of 65 may be more sensitive to side effects. Talk with your healthcare provider about any concerns about side effects that you may have.

Missed Dose

If you forget to inject your dose of Nucala on your scheduled day, inject it as soon as you remember and then resume your regular dosing schedule. Call your healthcare provider if you are unsure when to inject your Nucala. 

Overdose: What Happens If I Take Too Much Nucala?

Information on the effects of a Nucala overdose is lacking, but an increased risk of side effects may be a concern. Keep track of your dosing schedule to ensure that you administer your dose on the correct day. It may help to set up a reminder system (e.g., an alert on your phone). If you've taken more than your prescribed dose or you've administered your dose too soon, call your healthcare provider. If your symptoms feel life-threatening, call 911 immediately.

What Happens If I Overdose on Nucala?

If you think you or someone else may have overdosed on Nucala, call a healthcare provider or the Poison Control Center (800-222-1222). 

If someone collapses or isn't breathing after taking Nucala, call 911 immediately.



Precautions

Drug Content Provided and Reviewed by IBM Micromedex®

It is very important that your doctor check your or your child's progress at regular visits to make sure that this medicine is working properly and to check for unwanted effects.

Serious allergic reactions, including anaphylaxis and angioedema, which can be life-threatening and requires immediate medical attention. Tell your doctor right away if you or your child have cough, rash, itching skin, large, hive-like swelling on face, eyelids, lips, tongue, throat, hands, legs, feet, or sex organs, trouble breathing, trouble swallowing, or any swelling of your hands, face, or mouth after using this medicine.

This medicine will not stop an asthma attack that has already started. Your doctor may prescribe another medicine for you to use in case of an asthma attack.

This medicine may lead to herpes zoster infection (shingles). You may receive a vaccine before you start treatment. Tell your doctor if you have not had either chickenpox or the chickenpox vaccine.

If you use a corticosteroid medicine (inhaled or taken by mouth) to control your asthma, keep using it unless your doctor tells you otherwise.

What Are Reasons I Shouldn't Take Nucala?

Do not take Nucala if you are allergic to mepolizumab or any other ingredient in Nucala. Ask your pharmacist for a list of the ingredients if you are unsure and discuss with your healthcare provider.

Let your healthcare provider know if you have ever had or currently have a parasitic infection caused by worms (helminth infection). You will likely need to treat the infection before starting Nucala.

What Other Medications Interact With Nucala?

Nucala does not interact with most medications, but it's important to let your healthcare provider and pharmacist know about all the medicines you take, including over-the-counter, nonprescription products like supplements or plant-based medicines like herbal preparations.

What Medications Are Similar?

Nucala is a monoclonal antibody that decreases inflammation by targeting eosinophils—a type of white blood cell. Other monoclonal antibodies that work similarly to Nucala and treat similar conditions include:

  • Cinqair (reslizumab) - only approved for asthma treatment
  • Dupixent (dupilumab) - approved for treatment of asthma and chronic rhinosinusitis with nasal polyps
  • Fasenra (benralizumab) - only approved for asthma treatment

These products differ based on how often they're administered and side effects. Cinqair must be administered intravenously (IV), so you'd need to receive your dose at an infusion center. Cinqair is also only approved for adults. You and your healthcare provider will work together to determine which treatment is best for you.

Frequently Asked Questions

  • What is Nucala used for?

    Nucala is used to treat certain types of severe asthma (eosinophilic asthma) that has not responded to other treatments. Healthcare providers also prescribe Nucala to treat chronic rhinosinusitis with nasal polyps and other conditions that involve high levels of a certain type of white blood cell (eosinophils).

  • How does Nucala work?

    Nucala targets eosinophils—a type of white blood cell that is part of your immune system. When eosinophil levels become too high, inflammation can occur. Nucala helps lower eosinophil levels and reduce inflammation that can contribute to your symptoms.

  • What are the side effects of Nucala?

    The most common side effects of Nucala include headache, back pain, tiredness and injection site reactions (e.g., pain, redness, swelling, itching or burning). Some people taking Nucala to treat chronic rhinosinusitis with nasal polyps may also experience mouth, throat or joint pain.

How Can I Stay Healthy While Taking Nucala?

Our immune systems normally keep us healthy, but sometimes too much of a good thing can lead to trouble. Fortunately, Nucala helps to manage symptoms that arise from your immune system, decreasing the inflammation that can make your asthma or sinusitis symptoms worse.

If you take Nucala for asthma, it's important to remember that Nucala is a maintenance medication. It is not a rescue medication and will not treat a sudden asthma attack or breathing problems. Talk with your healthcare provider about what you should do when you have an asthma attack.

Medical Disclaimer

Verywell Health's drug information is meant for education purposes only and not intended as a replacement for medical advice, diagnosis, or treatment from a healthcare professional. Consult your doctor before taking any new medication(s). IBM Watson Micromedex provides some of the drug content, as indicated on the page.

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