Linked Life Data

14757489

Source:http://linkedlifedata.com/resource/pubmed/id/14757489

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2-3
pubmed:dateCreated
2004-2-3
pubmed:abstractText
The aim of this study was to assess the feasibility of using oral modified-release formulations for the purposes of site-specific targeting and regional drug absorption assessment in man. An immediate release pellet formulation containing ranitidine as the model drug of choice for the study was fabricated by extrusion-spheronisation, and then film coated with either the enteric polymer polyvinyl acetate phthalate or the bacteria-degradable polymer amylose, in combination with ethylcellulose, to effect drug release within the small intestine and colon, respectively. Optimised formulations were evaluated in vivo in ten healthy volunteers, who each received, on four separate occasions, the immediate release, small intestinal release and colonic release formulations (each equivalent to 150mg ranitidine), and an intravenous injection of ranitidine (equivalent to 50mg ranitidine). Blood samples were collected and assessed for ranitidine concentration, and radiolabelled placebo pellets were co-administered with the coated ranitidine pellets to monitor their gastrointestinal transit using a gamma camera. Ranitidine was rapidly released and absorbed from the immediate release formulation, whereas the enteric formulation (10% coat weight gain) delayed drug release until some or all of the pellets had emptied into the small intestine. The amylose-ethylcellulose coated formulation (coat ratio 1:3, coat weight gain 25%) retarded ranitidine release until the pellets had reached the colon. The mean absolute bioavailability of ranitidine from the immediate release, small intestinal release and colonic release formulations were 50.6, 46.1 and 5.5%, respectively. These data are in general agreement to those obtained from a previous regional intubation study. The present study therefore demonstrates the practical potential of utilising a non-invasive, formulation-based approach to assess drug absorption from different regions of the human gastrointestinal tract.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0928-0987
pubmed:author
pubmed:issnType
Print
pubmed:volume
21
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
179-89
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:14757489-Administration, Oral, pubmed-meshheading:14757489-Adult, pubmed-meshheading:14757489-Amylose, pubmed-meshheading:14757489-Biological Availability, pubmed-meshheading:14757489-Cellulose, pubmed-meshheading:14757489-Chemistry, Pharmaceutical, pubmed-meshheading:14757489-Colon, pubmed-meshheading:14757489-Cross-Over Studies, pubmed-meshheading:14757489-Drug Compounding, pubmed-meshheading:14757489-Excipients, pubmed-meshheading:14757489-Gastrointestinal Transit, pubmed-meshheading:14757489-Histamine H2 Antagonists, pubmed-meshheading:14757489-Humans, pubmed-meshheading:14757489-Intestinal Absorption, pubmed-meshheading:14757489-Intestine, Small, pubmed-meshheading:14757489-Male, pubmed-meshheading:14757489-Middle Aged, pubmed-meshheading:14757489-Ranitidine, pubmed-meshheading:14757489-Tablets, Enteric-Coated, pubmed-meshheading:14757489-Time Factors
pubmed:year
2004
pubmed:articleTitle
The use of formulation technology to assess regional gastrointestinal drug absorption in humans.
pubmed:affiliation
Department of Pharmaceutics, The School of Pharmacy, University of London, 29/39 Brunswick Square, London WC1N 1AX, UK. abdul.basit@ulsop.ac.uk
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't