Ibrutinib (Imbruvica) is a Bruton's tyrosine kinase (BTK) inhibitor indicated for the treatment of various B-cell malignancies and chronic graft-versus-host disease (cGVHD).
I. Common Side Effects
The most common adverse reactions (incidence ≥ 30%) of ibrutinib include thrombocytopenia, diarrhea, fatigue, musculoskeletal pain, neutropenia, rash, anemia, bruising and nausea.
In patients with chronic graft-versus-host disease, additional common reactions include fever, stomatitis, hemorrhage, abdominal pain, pneumonia and headache.
II. Serious Side Effects and Precautions
Hemorrhage
(1) Severe bleeding occurs in approximately 4% of patients, and concurrent use of anticoagulants or antiplatelet agents further increases this risk.
(2) Discontinue ibrutinib 3–7 days prior to surgery.
Infections
(1) Grade ≥ 3 infections occur in 21% of patients, including progressive multifocal leukoencephalopathy and Pneumocystis jirovecii pneumonia.
(2) Prophylactic anti-infective therapy should be considered for high-risk populations.
Cardiac Events
Approximately 3.7% of patients develop grade ≥ 3 atrial fibrillation, and 1.3% develop grade ≥ 3 heart failure; patients with pre-existing cardiac dysfunction are at higher risk.
Hypertension
(1) The incidence is 19%, of which 8% are grade ≥ 3.
(2) Blood pressure may increase cumulatively over time, requiring regular monitoring.
Hepatotoxicity
Drug-induced liver injury may occur; liver function should be monitored regularly, and the drug should be discontinued immediately if hepatotoxicity is suspected.
III. Side Effect Management Strategies
Dose Modification
In the event of grade ≥ 3 adverse events, adult patients with CLL/WM may reduce the dose from 420 mg to 280 mg or 140 mg; pediatric patients with cGVHD may reduce the dose from 240 mg/m² to 160 mg/m² or 80 mg/m².
Hemorrhage Management
(1) Avoid concurrent use of anticoagulants such as aspirin and warfarin.
(2) Suspend administration as directed by a physician prior to surgery.
Infection Prophylaxis
(1) Monitor body temperature and seek medical attention promptly if fever occurs.
(2) Administer prophylactic antibiotics or antiviral agents when necessary.
Diarrhea Management
(1) Increase fluid intake to prevent dehydration; notify a physician if diarrhea persists.
(2) Diarrhea resolves spontaneously in most patients, with a median duration of 7 days.
Cardiac Monitoring
Seek immediate medical evaluation with electrocardiography or echocardiography if palpitations, dizziness, chest pain, dyspnea or lower extremity edema occur.
IV. Storage Requirements
Capsules and Tablets
(1) Store at room temperature 20–25°C; short-term exposure to 15–30°C is permitted.
(2) Keep capsules in the original bottle with the cap tightly closed; retain tablets in the original carton.
Oral Suspension
(1) Store at 2–25°C; do not freeze.
(2) Use within 60 days after first opening; discard any unused portion after expiration.
General Instructions
(1) Keep all formulations out of reach of children.
(2) The suspension is supplied with a child-resistant cap; replace cap tightly after each use.
V. Important Administration Reminders
Administration Instructions
Take at the same time daily, swallow whole with a glass of water; do not open, chew or crush tablets or capsules.
Missed Dose
If a dose is missed, take it as soon as possible on the same day; resume the regular schedule the next day. Do not double the dose.
Dietary Instructions
Avoid consumption of grapefruit or Seville oranges, as they may increase drug concentrations.


