Toxicity of Imatinib

The most frequently reported drug-related adverse events are nausea, vomiting, edema, and muscle cramps
Most events are of mild-to-moderate grade, and only 2% to 5% of patients permanently discontinue therapy, most commonly because of skin rashes and elevations of transaminases
Edema can manifest at any site, most commonly in the ankles and periorbital tissues. Severe fluid retention (pleural effusion, pericardial effusion, pulmonary edema, and ascites) is reported in 1% to 2% of patients taking imatinib.
Neutropenia and thrombocytopenia are consistent findings in all studies in leukemia patients, with a higher frequency at doses ³750 mg.
(Reference : Goodman & Gillmans 11th edition)