 11. Exclusion 8 continued: g. Drugs are not recommended but can be used with caution; 1. Antacids: Use of H2 blockers and proton pump inhibitors is not recommended because systemic antacids H2 inhibitors, proton pump inhibitors decrease dasatinib absorption. Patients who require antacids should use short acting, locally active agents e.g., Maalox, Mylanta etc.. However, these agents should not be taken within either 2 hours before or 2 hours after the dasatinib dose. 2. Drugs prolong QT interval; erythromycin, clarithromycin, pentamidine, ondansetron, granisetron, and methadone. 