title: Total and free valproic acid: plasma level/dose ratio in monotherapy.
abstract: Free plasma level/dose ratio of valproic acid (L/D-F) can be more effective than total plasma level/dose ratio (L/D-T) in adjusting dosage regimens. The influence of age, dose, and plasma concentration have been studied on L/D-T and L/D-F ratios. L/D-T and L/D-F ratios from 67 outpatients under long-term monotherapy were obtained. Analytical data was carried out by fluorescent polarized immunoassay. L/D-T and L/D-F ratios do not vary according to age. L/D-T and L/D-F ratios decreased while the dosage increased; both ratios increased with an increase in total plasma level of valproic acid. Significant differences were found between L/D-T and L/D-F ratios. Dose and interindividual variations are the factors which most influence L/D ratios of valproic acid.
authors.affiliation: Clinical Pharmacology Department, University Hospital Virgen Macarena, Seville, Spain.
authors.forename: J A
authors.initials: JA
authors.lastname: Abadín
authors.forename: J A
authors.initials: JA
authors.lastname: Durán
authors.forename: A
authors.initials: A
authors.lastname: Sánchez
authors.forename: J S
authors.initials: JS
authors.lastname: Serrano
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000375:Aging / Q000378:metabolism; D002648:Child; D002675:Child, Preschool; D004305:Dose-Response Relationship, Drug; D004827:Epilepsy / Q000097:blood / Q000188:drug therapy*; D005260:Female; D016231:Fluorescence Polarization Immunoassay; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D012737:Sex Factors; D014635:Valproic Acid / Q000097:blood* / Q000627:therapeutic use
chemical_list: D014635:Valproic Acid