Hazardous agent. May cause bone marrow suppression (anemia, neutropenia, and thrombocytopenia). Cardiovascular effects possible (usually reported in comorbidities and/or risk factors). Dermatologic reactions (erythema multiforme and Stevens-Johnson syndrome) reported. Often associated with fluid retention, weight gain, and edema (use with caution in patients where fluid accumulation may be poorly tolerated, such as in cardiovascular disease (HF or hypertension) and pulmonary disease). May cause GI irritation. Severe hemorrhage reported with use, including GI hemorrhage and/or tumor hemorrhage. Hepatotoxicity might occur (may be severe). Acute liver failure also reported. Opportunistic infections might develop. Use with caution in bone marrow suppression. Use with caution in hepatic or renal impairment. Hypothyroidism reported in thyroidectomy patients (receiving thyroid hormone replacement therapy) during imatinib therapy. High potential for CYP interactions. Risk of severe superficial edema (e.g. rapid weight gain, facial edema, anasarca), severe fluid retention (i.e. pleural effusion, pericardial effusion, pulmonary edema, ascites), cerebral edema, increased intracranial pressure, and papilledema (including fatalities).