Mepolizumab Side Effects

Medically reviewed by Drugs.com. Last updated on Nov 9, 2023.

Applies to mepolizumab: subcutaneous powder for solution, subcutaneous solution.

Serious side effects of Mepolizumab

Along with its needed effects, mepolizumab may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking mepolizumab:

Incidence not known

• Blurred vision
• chest tightness
• confusion
• cough
• difficulty with breathing
• dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
• fast heartbeat
• hives or welts, itching, or skin rash
• large, hive-like swelling on the face, eyelids, lips, tongue, throat, hands, legs, feet, or sex organs
• noisy breathing
• painful blisters on the trunk of the body
• redness of the skin
• sweating
• unusual tiredness or weakness

Other side effects of Mepolizumab

Some side effects of mepolizumab may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

• Back pain
• bleeding, blistering, burning, coldness, discoloration of the skin, feeling of pressure, hives, infection, inflammation, itching, lumps, numbness, pain, rash, redness, scarring, soreness, stinging, swelling, tenderness, tingling, ulceration, or warmth at the injection site
• difficulty in moving
• headache
• joint pain
• muscle pain or stiffness
• sore throat

Less common

• Bladder pain
• bloody or cloudy urine
• chills
• diarrhea
• difficult, burning, or painful urination
• fever
• frequent urge to urinate
• general feeling of discomfort or illness
• loss of appetite
• lower back or side pain
• muscle aches or spasms
• nausea
• runny nose
• shivering
• skin rash, encrusted, scaly, and oozing
• sweating
• trouble sleeping
• upper abdominal or stomach pain
• vomiting

For Healthcare Professionals

Applies to mepolizumab: subcutaneous powder for injection, subcutaneous solution.

General

The more commonly reported side effects were headache, injection site reactions, and back pain.^[Ref]

Nervous system

Very common (10% or more): Headache (up to 19%)

Frequency not reported: Dizziness^[Ref]

Dizziness occurred in at least 3% of patients treated with this drug in a controlled, long-term clinical study.^[Ref]

Hypersensitivity

Common (1% to 10%): Systemic non-allergic/administration-related reactions (including rash, flushing, myalgia), systemic/hypersensitivity reactions (including rash, pruritus, headache, myalgia)

Frequency not reported: Allergic rhinitis, angioedema, urticaria^[Ref]

Many systemic reactions occurred on the day of dosing. Systemic reactions occurred in 10% of patients treated with this drug compared to 7% of placebo-treated patients. Non-allergic reactions occurred in 2% of patients given this drug versus 3% of patients with placebo; allergic systemic reactions occurred in 1% and 2% of patients given this drug or placebo, respectively.

Allergic rhinitis occurred in at least 3% of patients treated with this drug in a controlled, long-term clinical study.^[Ref]

Local

Common (1% to 10%): Injection site reactions (e.g., pain, swelling, erythema, itching, burning)^[Ref]

Injection site reactions occurred in 8% and 3% of patients given this drug or placebo, respectively. The reactions more commonly occurred within the first 3 injections, with a decrease in frequency on subsequent injections.^[Ref]

Immunologic

Common (1% to 10%): Influenza, anti-mepolizumab antibody formation

Frequency not reported: Viral infection^[Ref]

In a clinical trial, 6% of patients developed anti-mepolizumab antibodies; these antibodies were shown to slightly increase drug clearance, but the clinical relevance is unknown.

Viral infection occurred in at least 3% of patients treated with this drug in a controlled, long-term clinical study.^[Ref]

Dermatologic

Common (1% to 10%): Pruritus, eczema

Frequency not reported: Rash, flushing, herpes zoster reaction^[Ref]

Rash and herpes zoster occurred in at least 3% of patients treated with this drug in a controlled, long-term clinical study.^[Ref]

Musculoskeletal

Common (1% to 10%): Back pain, muscle spasms

Frequency not reported: Musculoskeletal pain, myalgia^[Ref]

Musculoskeletal pain occurred in at least 3% of patients treated with this drug in a controlled, long-term clinical study.^[Ref]

Gastrointestinal

Common (1% to 10%): Upper abdominal pain

Frequency not reported: Gastroenteritis, abdominal pain, nausea, toothache, vomiting^[Ref]

Gastroenteritis, abdominal pain, nausea, toothache, and vomiting occurred in at least 3% of patients treated with this drug in a controlled, long-term clinical study.^[Ref]

Other

Common (1% to 10%): Fatigue, pyrexia

Frequency not reported: Asthenia, ear infection^[Ref]

Asthenia, ear infection, and pyrexia occurred in at least 3% of patients treated with this drug in a controlled, long-term clinical study.^[Ref]

Genitourinary

Common (1% to 10%): Urinary tract infection^[Ref]

Respiratory

Common (1% to 10%): Lower respiratory tract infection, pharyngitis, nasal congestion

Frequency not reported: Bronchitis, dyspnea, nasopharyngitis, viral respiratory tract infection, bronchospasm^[Ref]

Bronchitis, dyspnea, lower respiratory tract infection, nasal congestion, nasopharyngitis, pharyngitis, and viral respiratory tract infection occurred in at least 3% of patients treated with this drug in a controlled, long-term clinical study.^[Ref]

Cardiovascular

Frequency not reported: Hypotension^[Ref]

Renal

Frequency not reported: Cystitis^[Ref]

Cystitis occurred in at least 3% of patients treated with this drug in a controlled, long-term clinical study.^[Ref]

Frequently asked questions

• How long does it take for Nucala to work?
• Can Nucala cause weight gain?
• Can Nucala be self-administered? How is it injected?
• What is Nucala (mepolizumab) used for and how is it given?

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.

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