In recently published guidelines, the Infectious Diseases Society of America (IDSA) recommends antifungal prophylaxis with posaconazole in HSCT recipients with GVHD who are at high risk for invasive aspergillosis and in patients with acute myelogenous leukemia or myelodysplastic syndrome who are at high risk for invasive aspergillosis. The IDSA guidelines state that itraconazole may be effective, but tolerability limits its use.