What the label lists and what reports show
Benralizumab side effects
Benralizumab's FDA label: “Most common adverse reactions (incidence greater than or equal to 5%): • Asthma: headache and pharyngitis.” FAERS holds 19,893 reports naming it through July 30, 2026; the reaction reported most often, leaving out the conditions it is used for, product-use terms and outcomes, is dyspnoea (1,999 reports).
- No generic listed
Check it at the source: the benralizumab FDA label on DailyMed (effective May 13, 2026, AstraZeneca Pharmaceuticals LP); the FDA FAERS public dashboard.
What does the patient leaflet say about side effects?
From the patient leaflet: What are the possible side effects of FASENRA?FASENRA may cause serious side effects, including: • allergic (hypersensitivity) reactions, including anaphylaxis. Serious allergic reactions can happen after you get your FASENRA injection. Allergic reactions can sometimes happen hours or days after you get your injection. Tell your healthcare provider or get emergency help right away if you get any of the following symptoms of an allergic reaction: o swelling of your face, mouth and tongue o breathing problems o fainting, dizziness, feeling lightheaded (low blood pressure) o rash o hives The most common side effects of FASENRA in: • adults and children with asthma include headache and sore throat. • adults with EGPA include headache. • adults and children with HES include headache, allergic reactions, and flu-like symptoms. These are not all the possible side effects of FASENRA. Call your doctor for medical advice about side effects. […]
Source: FDA drug label, AstraZeneca Pharmaceuticals LP, effective May 13, 2026 (SPL set da6aca1a-19ed-44a4-abb7-696c7d58b784), via openFDA; the full label on DailyMed
What does the label list?
From the label: adverse reactionsMost common adverse reactions (incidence greater than or equal to 5%): • Asthma: headache and pharyngitis.
Table 2. Adverse Reactions with FASENRA with Greater than or Equal to 3% Incidence in Patients with Asthma (SIROCCO and CALIMA)
| Adverse Reactions | FASENRA (N=822) % | Placebo (N=847) % |
|---|---|---|
| Headache | 8 | 6 |
| Pyrexia | 3 | 2 |
| Pharyngitis Pharyngitis was defined by the following terms: ‘Pharyngitis’, ‘Pharyngitis… | 5 | 3 |
| Hypersensitivity reactions Hypersensitivity Reactions were defined by the following… | 3 | 3 |
Rows and numbers as the label prints them, under its own column headings (the first rows of a longer table where it runs on). A reaction in a trial table is not necessarily caused by the medicine, and trials differ from everyday use.
From the label: adverse reactions, continuedThe following adverse reactions are described in greater detail in other sections: • Hypersensitivity Reactions [see Warnings and Precautions (5.1) ] Most common adverse reactions (incidence greater than or equal to 5%): • Asthma: headache and pharyngitis. ( 6.1 ) • EGPA: headache. ( 6.1 ) • HES: headache, hypersensitivity reactions, and influenza-like illness. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact AstraZeneca at 1-800-236-9933 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. Adult and Pediatric Patients 12 Years of Age and Older with Asthma Across three clinical trials (SIROCCO, CALIMA, and ZONDA) for asthma, 1,808 patients received at least 1 dose of FASENRA [see Clinical Studies (14.1) ]. The data described below reflect exposure to FASENRA in 1,663 patients, including 1,556 exposed for at least 24 weeks and 1,387 exposed for at least 48 weeks. …
Source: FDA drug label, AstraZeneca Pharmaceuticals LP, effective May 13, 2026 (SPL set da6aca1a-19ed-44a4-abb7-696c7d58b784), via openFDA; the full label on DailyMed
What do FAERS reports show?
19,893 reports list benralizumab among the medicines taken, each a report of something that happened, not proof the medicine caused it; 2,002 are coded as a death and 4,792 as a hospital stay. Counts follow how widely a medicine is used and watched, and they are not a measure of how risky it is. Of the 18 reactions below, 7 are named by the same term (in US spelling) in the label's adverse reactions, warnings or patient leaflet; a reaction the label does not name may still be there under another word, and a report does not show that the medicine caused it.
Reports received each year
The 25 most reported reactions
Source: FDA Adverse Event Reporting System (FAERS) via openFDA, reports through July 30, 2026; reactions as MedDRA preferred terms
What next?
- Benralizumab: the full record
- label, generics, price, shortages, recalls
- Report a side effect to the FDA
- MedWatch
- Side effects hub
- the most reported medicines and reactions