- Subjects must meet the following restrictions: Subjects may not have a concurrent medical condition which may increase the risk of toxicity, including pleural or pericardial effusion of any grade, or uncontrolled hypertension; Concomitant use of H2 blockers or proton pump inhibitors with dasatinib is not recommended (The use of antacids should be considered in place of H2 blockers or proton pump inhibitors in patients receiving dasatinib therapy); Patient must discontinue St. Johns Wort while receiving dasatinib therapy; Subjects must not use intravenous bisphosphonates during the first 8 weeks of dasatinib therapy due to risk of hypocalcemia; Subjects may not be receiving any restricted cytochrome P450 3A4 (CYP3A4) inhibitors (If the investigator feels that any of these agents should be given as uniquely useful for a clear diagnosis, the situation should be discussed with the Principal Investigator, and a clear monitoring program should be planned)