title: Duodenal and gastric delivery of levodopa in parkinsonism.
abstract: To clarify the influence of gastric emptying on levodopa-related motor fluctuations in Parkinson's disease, we assessed mobility and plasma levodopa concentrations in 10 patients during five modes of levodopa administration: (1) standard intermittent oral (SIO), (2) intermittent duodenal (ID), (3) continuous duodenal infusion (CDI), (4) continuous gastric infusion (CGI), and (5) controlled-release Sinemet (CR-4). The rank order from greatest to least for both percentage of time "on" and average mobility score was CDI, CGI, ID, CR-4, and SIO. The rank order for variance of means, a measure of fluctuation, from least to greatest for mobility was CDI, CGI, CR-4, ID, SIO, and for plasma levodopa concentrations was CDI, CGI, ID, SIO, and CR-4. The results demonstrate that it is possible to produce very steady plasma concentrations of levodopa with a corresponding reduction in motor fluctuations by continuous intraduodenal administration of the drug. This mode of delivery is an ideal model for the development of optimal continuous-release preparations of levodopa. Other enteral routes have produced a more variable plasma levodopa concentration and clinical response.
authors.affiliation: Department of Neurology, University of Rochester School of Medicine and Dentistry, NY 14642.
authors.forename: R
authors.initials: R
authors.lastname: Kurlan
authors.forename: J G
authors.initials: JG
authors.lastname: Nutt
authors.forename: W R
authors.initials: WR
authors.lastname: Woodward
authors.forename: K
authors.initials: K
authors.lastname: Rothfield
authors.forename: D
authors.initials: D
authors.lastname: Lichter
authors.forename: C
authors.initials: C
authors.lastname: Miller
authors.forename: J H
authors.initials: JH
authors.lastname: Carter
authors.forename: I
authors.initials: I
authors.lastname: Shoulson
mesh_terms: D000284:Administration, Oral; D004334:Drug Administration Schedule; D004386:Duodenum; D005746:Gastric Emptying; D006801:Humans; D007263:Infusions, Parenteral; D007980:Levodopa / Q000008:administration & dosage* / Q000097:blood / Q000627:therapeutic use; D010300:Parkinson Disease / Q000188:drug therapy*; D013270:Stomach
chemical_list: D007980:Levodopa