What the label lists and what reports show
Ibrutinib side effects
Ibrutinib's FDA label: “The most common (≥30%) adverse reactions in patients with B-cell malignancies are thrombocytopenia, diarrhea, fatigue, musculoskeletal pain, neutropenia, rash, anemia, bruising, and nausea ( 6 ).” FAERS holds 80,310 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 fatigue (4,752 reports).
- No generic listed
Check it at the source: the ibrutinib FDA label on DailyMed (effective October 21, 2025); 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 IMBRUVICA?IMBRUVICA may cause serious side effects, including: Bleeding problems (hemorrhage) are common during treatment with IMBRUVICA and can also be serious and may lead to death. Your risk of bleeding may increase if you are also taking a blood thinner medicine. Tell your healthcare provider if you have any signs of bleeding, including: blood in your stools or black stools (looks like tar) pink or brown urine unexpected bleeding, or bleeding that is severe or that you cannot control vomit blood or vomit looks like coffee grounds cough up blood or blood clots increased bruising, or small red or purple spots on the skin dizziness weakness confusion change in your speech headache that lasts a long time or severe headache Infections can happen during treatment with IMBRUVICA. These infections can be serious and may lead to death. […]
Source: FDA drug label, Pharmacyclics LLC, effective October 21, 2025 (SPL set 0dfd0279-ff17-4ea9-89be-9803c71bab44), via openFDA; the full label on DailyMed
What does the label list?
From the label: adverse reactionsThe most common (≥30%) adverse reactions in patients with B-cell malignancies are thrombocytopenia, diarrhea, fatigue, musculoskeletal pain, neutropenia, rash, anemia, bruising, and nausea ( 6 ).
Table 9: Adverse Reactions Reported in ≥ 10% of Patients in the IMBRUVICA Treated Arm in Patients with CLL/SLL in RESONATE-2
| Reaction | All Grades (%) | Grade 3 or Higher (%) | All Grades (%) | Grade 3 or Higher (%) |
|---|---|---|---|---|
| Diarrhea | 42 | 4 | 17 | 0 |
| Nausea | 22 | 1 | 39 | 1 |
| Constipation | 16 | 1 | 16 | 0 |
| Stomatitis | 14 | 1 | 4 | 1 |
| Vomiting | 13 | 0 | 20 | 1 |
| Abdominal pain | 13 | 3 | 11 | 1 |
| Dyspepsia | 11 | 0 | 2 | 0 |
| Musculoskeletal pain | 36 | 4 | 20 | 0 |
| Arthralgia | 16 | 1 | 7 | 1 |
| Muscle spasms | 11 | 0 | 5 | 0 |
| Fatigue | 30 | 1 | 38 | 5 |
| Peripheral edema | 19 | 1 | 9 | 0 |
| Pyrexia | 17 | 0 | 14 | 2 |
| Cough | 22 | 0 | 15 | 0 |
| Dyspnea | 10 | 1 | 10 | 0 |
| Rash | 21 | 4 | 12 | 2 |
| Bruising | 19 | 0 | 7 | 0 |
| Dry eye | 17 | 0 | 5 | 0 |
| Lacrimation increased | 13 | 0 | 6 | 0 |
| Vision blurred | 13 | 0 | 8 | 0 |
| Visual acuity reduced | 11 | 0 | 2 | 0 |
| Upper respiratory tract infection | 17 | 2 | 17 | 2 |
| Skin infection | 15 | 2 | 3 | 1 |
| Pneumonia | 14 | 8 | 7 | 4 |
| Urinary tract infections | 10 | 1 | 8 | 1 |
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 clinically significant adverse reactions are described elsewhere in the labeling: Hemorrhage [see Warnings and Precautions ( 5.1 )] Infections [see Warnings and Precautions ( 5.2 )] Cardiac Arrhythmias, Cardiac Failure, and Sudden Death [see Warnings and Precautions ( 5.3 )] Hypertension [see Warnings and Precautions ( 5.4 )] Cytopenias [see Warnings and Precautions ( 5.5 )] Second Primary Malignancies [see Warnings and Precautions ( 5.6 )] Hepatotoxicity, including DILI [see Warning s and Precautions ( 5.7 )] Tumor Lysis Syndrome [see Warnings and Precautions ( 5.8 )] The most common (≥30%) adverse reactions in patients with B-cell malignancies are thrombocytopenia, diarrhea, fatigue, musculoskeletal pain, neutropenia, rash, anemia, bruising, and nausea ( 6 ). The most common (≥20%) adverse reactions in adult or pediatric patients with cGVHD are fatigue, anemia, bruising, diarrhea, thrombocytopenia, musculoskeletal pain, pyrexia, muscle spasms, stomatitis, hemorrhage, nausea, abdominal pain, pneumonia, and headache ( 6 ). To report SUSPECTED ADVERSE REACTIONS, contact AbbVie at 1-800-633-9110 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. …
Source: FDA drug label, Pharmacyclics LLC, effective October 21, 2025 (SPL set 0dfd0279-ff17-4ea9-89be-9803c71bab44), via openFDA; the full label on DailyMed
What do FAERS reports show?
80,310 reports list ibrutinib among the medicines taken, each a report of something that happened, not proof the medicine caused it; 13,715 are coded as a death and 26,719 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 20 reactions below, 15 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?
- Ibrutinib: 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