OBJECTIVE: To study the effect of erythromycin on metabolism of quetiapine in Chinese suffering from schizophrenia. METHODS: Nineteen patients received multiple doses of quetiapine (200 mg, twice daily) with or without co-administered erythromycin (500 mg, three times daily). Blood samples were collected at specified time intervals for determination of plasma concentrations of quetiapine and some of its metabolites. RESULTS: With erythromycin co-administration: for quetiapine, maximal plasma concentration (Cmax), area under concentration-time curve of 0-infinity h (AUC0-infinity) and terminal-phase elimination half-life time (t1/2) increased 68, 129 and 92%, respectively, and clearance (CL) and terminal elimination rate constant (Ke) decreased 52% and 55%, respectively; for quetiapine sulfoxide (QTP-SF), Cmax, AUC0-infinity and AUC ratio decreased 64, 23, and 70%, respectively, and t1/2 increased 211%; for 7-hydroxy-quetiapine (QTP-H), Ke and AUC ratio decreased 61% and 45%, respectively, and t1/2 increased 203%; for 7-hydroxy-N-desalkyl-quetiapine (QTP-ND), Cmax, AUC0-infinity and AUC ratio decreased 36, 40 and 71%, respectively. CONCLUSION: Erythromycin has a noticeable effect on the metabolism of quetiapine. When quetiapine is co-administered with CYP3A inhibitors such as erythromycin, the dosing regimen should be modified according to quetiapine TDM.
OBJECTIVE: To study the effect of erythromycin on metabolism of quetiapine in Chinese suffering from schizophrenia. METHODS: Nineteen patients received multiple doses of quetiapine (200 mg, twice daily) with or without co-administered erythromycin (500 mg, three times daily). Blood samples were collected at specified time intervals for determination of plasma concentrations of quetiapine and some of its metabolites. RESULTS: With erythromycin co-administration: for quetiapine, maximal plasma concentration (Cmax), area under concentration-time curve of 0-infinity h (AUC0-infinity) and terminal-phase elimination half-life time (t1/2) increased 68, 129 and 92%, respectively, and clearance (CL) and terminal elimination rate constant (Ke) decreased 52% and 55%, respectively; for quetiapine sulfoxide (QTP-SF), Cmax, AUC0-infinity and AUC ratio decreased 64, 23, and 70%, respectively, and t1/2 increased 211%; for 7-hydroxy-quetiapine (QTP-H), Ke and AUC ratio decreased 61% and 45%, respectively, and t1/2 increased 203%; for 7-hydroxy-N-desalkyl-quetiapine (QTP-ND), Cmax, AUC0-infinity and AUC ratio decreased 36, 40 and 71%, respectively. CONCLUSION:Erythromycin has a noticeable effect on the metabolism of quetiapine. When quetiapine is co-administered with CYP3A inhibitors such as erythromycin, the dosing regimen should be modified according to quetiapine TDM.
Authors: B J McConville; L A Arvanitis; P T Thyrum; C Yeh; L A Wilkinson; R O Chaney; K D Foster; M T Sorter; L M Friedman; K L Brown; J E Heubi Journal: J Clin Psychiatry Date: 2000-04 Impact factor: 4.384
Authors: Yuanyuan Wang; Muh Akbar Bahar; Anouk M E Jansen; Janwillem W H Kocks; Jan-Willem C Alffenaar; Eelko Hak; Bob Wilffert; Sander D Borgsteede Journal: J Antimicrob Chemother Date: 2019-10-01 Impact factor: 5.790