While you are taking dasatinib, you will be given a drug diary. In this diary, you will write down the date, the time, and the number of dasatinib tablets taken. Certain drugs and herbal supplements may not be taken while you are receiving dasatinib. These drugs could affect how your body breaks down dasatinib, which could have a bad effect on you. Your doctor will give you a list of drugs and herbal supplements that you must not take while on this study. You must tell your doctor before taking any new drugs while on this study.