title: Little effects of low dosage of levomepromazine on plasma risperidone levels.
abstract: In the present study, we investigated the effects of levomepromazine on plasma risperidone concentrations in a steady state. Twenty patients taking risperidone at a stable dose for more than 2 weeks who were considered to require levomepromazine coadministration were selected. The scores of excitement in BPRS significantly decreased 2 weeks after the coadministration of levomepromazine. Plasma risperidone concentrations and the ratio of risperidone and 9-hydroxyrisperidone (risperidone/9-hydroxyrisperidone) did not change between before and 2 weeks after the coadministration of levomepromazine. The extrapyramidal symptoms were not worsened by the coadministration of levomepromazine. These results suggest that a low dosage of levomepromazine, use as a sedative adjuvant to risperidone treatment, have no statistically significant effect on the trough plasma concentrations of risperidone.
authors.forename: R
authors.initials: R
authors.lastname: Yoshimura
authors.forename: K
authors.initials: K
authors.lastname: Shinkai
authors.forename: S
authors.initials: S
authors.lastname: Kakihara
authors.forename: M
authors.initials: M
authors.lastname: Goto
authors.forename: Y
authors.initials: Y
authors.lastname: Yamada
authors.forename: K
authors.initials: K
authors.lastname: Kaji
authors.forename: N
authors.initials: N
authors.lastname: Ueda
authors.forename: J
authors.initials: J
authors.lastname: Nakamura
mesh_terms: D000293:Adolescent; D000328:Adult; D014150:Antipsychotic Agents / Q000097:blood* / Q000378:metabolism; D010054:Brief Psychiatric Rating Scale; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D008297:Male; D008728:Methotrimeprazine / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use*; D008875:Middle Aged; D011618:Psychotic Disorders / Q000188:drug therapy*; D018967:Risperidone / Q000097:blood* / Q000378:metabolism
chemical_list: D014150:Antipsychotic Agents; D008728:Methotrimeprazine; D018967:Risperidone