Abstract
Midazolam is metabolized by cytochrome P450 (CYP) 3A4, and voriconazole inhibits CYP3A4 activity. Although it is well known that midazolam interacts with voriconazole, there have been no reports about the sedative effect of midazolam when administered in combination with voriconazole, followed by discontinuation of voriconazole. Here, we describe one such case.
The patient was administered voriconazole followed by midazolam with the aim of inducing sedation. The drugs were administered for 4 days, after which voriconazole was discontinued. Although the midazolam administration rate remained constant, the patient recovered consciousness approximately 24 hours after the last injection of voriconazole. Therefore, the flow rate of midazolam was increased to a rate 8 to 9.7 times higher than that used during the combined administration of voriconazole and midazolam. Thus, this case shows that it is necessary to increase the dosage of midazolam and to monitor patients carefully when voriconazole is discontinued after being administered in combination with midazolam.
