title: Multiple inductive effects of carbamazepine on combined therapy with paliperidone and amlodipine.
abstract: OBJECTIVE
  Carbamazepine is a potent inducer of cytochrome P450 3A and P-glycoprotein. However, there are no reports of the effects of carbamazepine on more than one co-administered drug.
  
  
  METHODS
  A 53-year-old female patient with schizophrenia and hypertension was on paliperidone 12 mg/day and amlodipine 5 mg/day. When carbamazepine was added to this prescription, the plasma concentrations of both drugs decreased dramatically in a dose-dependent manner. Although the patient's psychotic symptoms did not change, as a result, her mean blood pressure increased to 160·1/103·6 mmHg from 138·4/91·4 mmHg at a carbamazepine dose of 600 mg/day.
  
  
  CONCLUSIONS
  Theses cases show the effect of carbamazepine induction on two drugs simultaneously. Care is required when carbamazepine is added to drug regimens including paliperidone or amlodipine alone or together.
authors.affiliation: Department of Pharmacy, Akita University Hospital, Akita, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Akamine
authors.affiliation: Department of Hospital Pharmacy, Faculty of Medicine, University of the Ryukyus, Okinawa, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Uehara
authors.affiliation: Department of Pharmacy, Akita University Hospital, Akita, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Miura
authors.affiliation: Department of Neuropsychiatry, Hirosaki University School of Medicine, Hirosaki, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Yasui-Furukori
authors.affiliation: Department of Pharmacy, Zikeikai-Aoimori Hospital, Aomori, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Uno
mesh_terms: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000187:drug effects / Q000378:metabolism; D017311:Amlodipine / Q000008:administration & dosage / Q000493:pharmacokinetics* / Q000627:therapeutic use; D014150:Antipsychotic Agents / Q000627:therapeutic use; D001794:Blood Pressure / Q000187:drug effects; D002220:Carbamazepine / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D051544:Cytochrome P-450 CYP3A / Q000187:drug effects / Q000378:metabolism; D065701:Cytochrome P-450 CYP3A Inducers / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D005260:Female; D006801:Humans; D006973:Hypertension / Q000188:drug therapy; D008875:Middle Aged; D000068882:Paliperidone Palmitate / Q000008:administration & dosage / Q000493:pharmacokinetics* / Q000627:therapeutic use; D012559:Schizophrenia / Q000188:drug therapy
chemical_list: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D014150:Antipsychotic Agents; D065701:Cytochrome P-450 CYP3A Inducers; D017311:Amlodipine; D002220:Carbamazepine; D051544:Cytochrome P-450 CYP3A; D000068882:Paliperidone Palmitate
keywords: CYP3A; P-glycoprotein; carbamazepine; pharmacodynamics; pharmacokinetics