Invasive aspergillosis (IA) is a fatal infectious complication among immunocompromised patients. Aspergillus terreus, the fourth common species can be difficult to treat due to a unique resistance pattern. To date, there has been no report on safety and dose adjustment when intravenous posaconazole is selected in hepatic and renal impairment patient. | A case report of intravenous posaconazole in hepatic and renal impairment patient with invasive Aspergillus terreus infection: Safety and role of therapeutic drug monitoring